Drug Therapy

Widespread opioid use disorder (OUD) has spawned new epidemics of hepatitis C virus (HCV) and HIV infections as well as increased hospitalizations for bacteremia, endocarditis, skin and soft tissue infections, and osteomyelitis, according to a report arising from a National Academies of Science, Engineering and Medicine (NASEM) workshop titled Integrating Infectious Disease Considerations with Response to the Opioid Epidemic.

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Optimal treatment of these infections is often impeded by untreated OUD, Sandra A. Springer, MD, and her colleagues wrote in an article published online in the Annals of Internal Medicine. Failing to address OUD can result in longer hospital stays; frequent readmissions because of a lack of adherence to antibiotic regimens; or reinfection, morbidity, and high costs. “Medical settings that manage such infections offer a potential means of engaging people in treatment of OUD; however, few providers and hospitals treating such infections have the needed resources and capabilities,” Dr. Springer, director, infectious disease outpatient clinic, Veterans Administration, Newington, and of Yale University, New Haven, both in Conn., and her colleagues wrote.

The authors outlined five action steps resulting from the NASEM workshop:

• Implement screening for OUD in all relevant health care settings.
• For patients with positive screening results, immediately prescribe effective medication for OUD and/or opioid withdrawal symptoms.
• Develop hospital-based protocols that facilitate OUD treatment initiation and linkage to community-based treatment upon discharge.
• Hospitals, medical schools, physician assistant schools, nursing schools, and residency programs should increase training to identify and treat OUD.
• Increase access to addiction care and funding to states to provide effective medications to treat OUD.

Opioid withdrawal and pain syndromes should be addressed with opioid agonist therapies to optimize infectious disease (ID) treatment and relieve pain, according to Dr. Springer and her colleagues. In addition, “Because ID specialists are likely to be consulted for anyone requiring long-term antibiotic therapy or patients with HIV and HCV infection, OUD screening should be a standard part of an ID consult assessment,” the authors wrote.

“All health care providers have a role in combating the OUD epidemic and its ID consequences. Those who treat infectious complications of OUD are well suited to screen for OUD and begin treatment with effective FDA-approved medications,” the authors concluded.

The workshop was held in March 2018 in Washington and videos and slide presentations from the meeting are available.

Dr. Springer and her colleagues reported grant funding from the National Institutes of Health, but no commercial conflicts.
 

[email protected]

SOURCE: Springer SA et al. Ann Intern Med. 2018 Jul 13. doi: 10.7326/M18-1203.

Widespread opioid use disorder (OUD) has spawned new epidemics of hepatitis C virus (HCV) and HIV infections as well as increased hospitalizations for bacteremia, endocarditis, skin and soft tissue infections, and osteomyelitis, according to a report arising from a National Academies of Science, Engineering and Medicine (NASEM) workshop titled Integrating Infectious Disease Considerations with Response to the Opioid Epidemic.

Hailshadow/iStock/Getty Images

Optimal treatment of these infections is often impeded by untreated OUD, Sandra A. Springer, MD, and her colleagues wrote in an article published online in the Annals of Internal Medicine. Failing to address OUD can result in longer hospital stays; frequent readmissions because of a lack of adherence to antibiotic regimens; or reinfection, morbidity, and high costs. “Medical settings that manage such infections offer a potential means of engaging people in treatment of OUD; however, few providers and hospitals treating such infections have the needed resources and capabilities,” Dr. Springer, director, infectious disease outpatient clinic, Veterans Administration, Newington, and of Yale University, New Haven, both in Conn., and her colleagues wrote.

The authors outlined five action steps resulting from the NASEM workshop:

• Implement screening for OUD in all relevant health care settings.
• For patients with positive screening results, immediately prescribe effective medication for OUD and/or opioid withdrawal symptoms.
• Develop hospital-based protocols that facilitate OUD treatment initiation and linkage to community-based treatment upon discharge.
• Hospitals, medical schools, physician assistant schools, nursing schools, and residency programs should increase training to identify and treat OUD.
• Increase access to addiction care and funding to states to provide effective medications to treat OUD.

Opioid withdrawal and pain syndromes should be addressed with opioid agonist therapies to optimize infectious disease (ID) treatment and relieve pain, according to Dr. Springer and her colleagues. In addition, “Because ID specialists are likely to be consulted for anyone requiring long-term antibiotic therapy or patients with HIV and HCV infection, OUD screening should be a standard part of an ID consult assessment,” the authors wrote.

“All health care providers have a role in combating the OUD epidemic and its ID consequences. Those who treat infectious complications of OUD are well suited to screen for OUD and begin treatment with effective FDA-approved medications,” the authors concluded.

The workshop was held in March 2018 in Washington and videos and slide presentations from the meeting are available.

Dr. Springer and her colleagues reported grant funding from the National Institutes of Health, but no commercial conflicts.
 

[email protected]

SOURCE: Springer SA et al. Ann Intern Med. 2018 Jul 13. doi: 10.7326/M18-1203.

Widespread opioid use disorder (OUD) has spawned new epidemics of hepatitis C virus (HCV) and HIV infections as well as increased hospitalizations for bacteremia, endocarditis, skin and soft tissue infections, and osteomyelitis, according to a report arising from a National Academies of Science, Engineering and Medicine (NASEM) workshop titled Integrating Infectious Disease Considerations with Response to the Opioid Epidemic.

Hailshadow/iStock/Getty Images

Optimal treatment of these infections is often impeded by untreated OUD, Sandra A. Springer, MD, and her colleagues wrote in an article published online in the Annals of Internal Medicine. Failing to address OUD can result in longer hospital stays; frequent readmissions because of a lack of adherence to antibiotic regimens; or reinfection, morbidity, and high costs. “Medical settings that manage such infections offer a potential means of engaging people in treatment of OUD; however, few providers and hospitals treating such infections have the needed resources and capabilities,” Dr. Springer, director, infectious disease outpatient clinic, Veterans Administration, Newington, and of Yale University, New Haven, both in Conn., and her colleagues wrote.

The authors outlined five action steps resulting from the NASEM workshop:

• Implement screening for OUD in all relevant health care settings.
• For patients with positive screening results, immediately prescribe effective medication for OUD and/or opioid withdrawal symptoms.
• Develop hospital-based protocols that facilitate OUD treatment initiation and linkage to community-based treatment upon discharge.
• Hospitals, medical schools, physician assistant schools, nursing schools, and residency programs should increase training to identify and treat OUD.
• Increase access to addiction care and funding to states to provide effective medications to treat OUD.

Opioid withdrawal and pain syndromes should be addressed with opioid agonist therapies to optimize infectious disease (ID) treatment and relieve pain, according to Dr. Springer and her colleagues. In addition, “Because ID specialists are likely to be consulted for anyone requiring long-term antibiotic therapy or patients with HIV and HCV infection, OUD screening should be a standard part of an ID consult assessment,” the authors wrote.

“All health care providers have a role in combating the OUD epidemic and its ID consequences. Those who treat infectious complications of OUD are well suited to screen for OUD and begin treatment with effective FDA-approved medications,” the authors concluded.

The workshop was held in March 2018 in Washington and videos and slide presentations from the meeting are available.

Dr. Springer and her colleagues reported grant funding from the National Institutes of Health, but no commercial conflicts.
 

[email protected]

SOURCE: Springer SA et al. Ann Intern Med. 2018 Jul 13. doi: 10.7326/M18-1203.

Study Overview

Objective. To assess usability and patient perceptions of the sarilumab auto-injector device  (“sarilumab pen”) among patients with moderate-to-severe rheumatoid arthritis (RA).

Design. 12-week, randomized, parallel-group usability study.

Setting and participants. The study was conducted at 53 centers in 6 countries. Inclusion criteria were a diagnosis of RA (as defined by American College of Rheumatology/ European League Against Rheumatism 2010 Criteria) of ≥ 3-month disease duration, willing and able to self inject, continuous treatment with 1 or a combination of nonbiologic disease modifying antirheumatic drugs (except leflunomide in combination with methotrexate); and moderatly to severely active RA, defined as 4/66 swollen joint, 4/68 tender joints, and high-sensitivity C-reactive protein (hsCRP) measurement ≥ 4 mg/L. Exclusion criteria were age

Patients were randomized 1:1:1:1 to sarilumamb 150 or 200 mg every 2 weeks administered by single-use, disposable, prefilled pen or pre-filled syringe. Randomization method was not reported.

Main outcomes measures. The primary endpoint was number of “product technical failures” (PTFs). Patients randomized to the pen were given a diary that had questions related to their ability to remove the cap, start the injection, and complete the injection. Participants were asked to answer the questions each time they used the pen. If the response was “no” to any of the 3 questions, this was considered a “product technical complaint” (PTC). PTCs that had a validated technical cause based on pen evaluation and analysis were considered PTFs.

In addition, patient perceptions and satisfaction with the pen were assessed via questionnaire. At baseline, patients were asked about injections and prior experience with self-injection, and at 12 weeks they were asked about their experiences in using the pen. Other outcomes assessed included adverse events and pharmokinetic parameters.

Results. 217 participants were enrolled: 108 patients were in the pen group (56 randomized to 150 mg and 52 randomized to 200 mg) and 109 were in the syringe group (53 randomized to 150 mg and 56 randomized to 200 mg). Completion rates were similar among groups. Sixteen patients discontinued due to treatment-emergent adverse events. There were no PTFs. There was one PTC, in which the user accidently bumped the pen, which expelled the drug onto the floor.

At baseline, before the first injection, the majority of patients reported that they were not afraid of needles (58%), had past experience with self-injections (55%), and were either “very confident” or “extremely confident” regarding self-injections (55%). After the 12-week assessment phase, when asked about their overall level of satisfaction, 98% of patients reported they were “satisfied” or “very satisfied” with the sarilumab pen.

Treatment emergent adverse events occurred in 66% of patients, with no clinically meaningful differences leading to discontinuation in the pen and syringe groups. The most common adverse events were infections and neutropenia.

Conclusion. Patients successfully completed self-injections with the sarilumab pen and found it easy to use.

Commentary

Rheumatoid arthritis (RA) is a common immune-mediated disease characterized by chronically progressive inflammation and destruction of joints and associated structures, resulting in significant morbidity, mortality, and disability. Improved understanding of RA disease pathogenesis in recent years has led to the development of new biologic treatments designed to target specific elements of the RA inflammatory response.

Sarilumab is an interleukin-6 blocker that was approved in the US in 2017 for the treatment of adult patients with moderately to severely active RA who have had an inadequate response or intolerance to one or more disease-modifying antirheumatic drugs. While a syringe form of this drug is currently available, at the time of this writing the pen has not yet been released.

In this real-world usability study sponsored by Sanofi, there were no technical difficulties with using the pen. Most patients thought the pen was easy or very easy to use, and safety and effeicacy appeared to be generally comparable between the pen and syringe. The pen also offers safety protection features that prevent needlestick injury.

The authors of the current study noted that results from previous studies have shown that patients with RA favor treatment devices that are easy to use, convenient, less painful, and take less time to use, and patients have demonstrated a preference for autoinjector devices over more conventional methods of treatment administration [1–3], such as syringes. Pens have been well accepted for the treatment of other chronic health conditions, including diabetes mellitus, migraine headaches, and growth hormone deficiency, and subcutaneous administration of a tumor necrosis factor (TNF) inhibitor via pen has also been accepted for the treatment of RA [1]. As RA requires lifelong treatment, the use of a pen that is ergonomically designed to take into account the manual dexterity issues relevant to this patient population could potentially enhance compliance.

Applications for Clinical Practice

A prefilled pen was well accepted and associated with favorable patient perceptions, indicating that this delivery system may be a viable option for RA patients who are prescribed sarilumab.

Study Overview

Objective. To assess usability and patient perceptions of the sarilumab auto-injector device  (“sarilumab pen”) among patients with moderate-to-severe rheumatoid arthritis (RA).

Design. 12-week, randomized, parallel-group usability study.

Setting and participants. The study was conducted at 53 centers in 6 countries. Inclusion criteria were a diagnosis of RA (as defined by American College of Rheumatology/ European League Against Rheumatism 2010 Criteria) of ≥ 3-month disease duration, willing and able to self inject, continuous treatment with 1 or a combination of nonbiologic disease modifying antirheumatic drugs (except leflunomide in combination with methotrexate); and moderatly to severely active RA, defined as 4/66 swollen joint, 4/68 tender joints, and high-sensitivity C-reactive protein (hsCRP) measurement ≥ 4 mg/L. Exclusion criteria were age

Patients were randomized 1:1:1:1 to sarilumamb 150 or 200 mg every 2 weeks administered by single-use, disposable, prefilled pen or pre-filled syringe. Randomization method was not reported.

Main outcomes measures. The primary endpoint was number of “product technical failures” (PTFs). Patients randomized to the pen were given a diary that had questions related to their ability to remove the cap, start the injection, and complete the injection. Participants were asked to answer the questions each time they used the pen. If the response was “no” to any of the 3 questions, this was considered a “product technical complaint” (PTC). PTCs that had a validated technical cause based on pen evaluation and analysis were considered PTFs.

In addition, patient perceptions and satisfaction with the pen were assessed via questionnaire. At baseline, patients were asked about injections and prior experience with self-injection, and at 12 weeks they were asked about their experiences in using the pen. Other outcomes assessed included adverse events and pharmokinetic parameters.

Results. 217 participants were enrolled: 108 patients were in the pen group (56 randomized to 150 mg and 52 randomized to 200 mg) and 109 were in the syringe group (53 randomized to 150 mg and 56 randomized to 200 mg). Completion rates were similar among groups. Sixteen patients discontinued due to treatment-emergent adverse events. There were no PTFs. There was one PTC, in which the user accidently bumped the pen, which expelled the drug onto the floor.

At baseline, before the first injection, the majority of patients reported that they were not afraid of needles (58%), had past experience with self-injections (55%), and were either “very confident” or “extremely confident” regarding self-injections (55%). After the 12-week assessment phase, when asked about their overall level of satisfaction, 98% of patients reported they were “satisfied” or “very satisfied” with the sarilumab pen.

Treatment emergent adverse events occurred in 66% of patients, with no clinically meaningful differences leading to discontinuation in the pen and syringe groups. The most common adverse events were infections and neutropenia.

Conclusion. Patients successfully completed self-injections with the sarilumab pen and found it easy to use.

Commentary

Rheumatoid arthritis (RA) is a common immune-mediated disease characterized by chronically progressive inflammation and destruction of joints and associated structures, resulting in significant morbidity, mortality, and disability. Improved understanding of RA disease pathogenesis in recent years has led to the development of new biologic treatments designed to target specific elements of the RA inflammatory response.

Sarilumab is an interleukin-6 blocker that was approved in the US in 2017 for the treatment of adult patients with moderately to severely active RA who have had an inadequate response or intolerance to one or more disease-modifying antirheumatic drugs. While a syringe form of this drug is currently available, at the time of this writing the pen has not yet been released.

In this real-world usability study sponsored by Sanofi, there were no technical difficulties with using the pen. Most patients thought the pen was easy or very easy to use, and safety and effeicacy appeared to be generally comparable between the pen and syringe. The pen also offers safety protection features that prevent needlestick injury.

The authors of the current study noted that results from previous studies have shown that patients with RA favor treatment devices that are easy to use, convenient, less painful, and take less time to use, and patients have demonstrated a preference for autoinjector devices over more conventional methods of treatment administration [1–3], such as syringes. Pens have been well accepted for the treatment of other chronic health conditions, including diabetes mellitus, migraine headaches, and growth hormone deficiency, and subcutaneous administration of a tumor necrosis factor (TNF) inhibitor via pen has also been accepted for the treatment of RA [1]. As RA requires lifelong treatment, the use of a pen that is ergonomically designed to take into account the manual dexterity issues relevant to this patient population could potentially enhance compliance.

Applications for Clinical Practice

A prefilled pen was well accepted and associated with favorable patient perceptions, indicating that this delivery system may be a viable option for RA patients who are prescribed sarilumab.

Study Overview

Objective. To assess usability and patient perceptions of the sarilumab auto-injector device  (“sarilumab pen”) among patients with moderate-to-severe rheumatoid arthritis (RA).

Design. 12-week, randomized, parallel-group usability study.

Setting and participants. The study was conducted at 53 centers in 6 countries. Inclusion criteria were a diagnosis of RA (as defined by American College of Rheumatology/ European League Against Rheumatism 2010 Criteria) of ≥ 3-month disease duration, willing and able to self inject, continuous treatment with 1 or a combination of nonbiologic disease modifying antirheumatic drugs (except leflunomide in combination with methotrexate); and moderatly to severely active RA, defined as 4/66 swollen joint, 4/68 tender joints, and high-sensitivity C-reactive protein (hsCRP) measurement ≥ 4 mg/L. Exclusion criteria were age

Patients were randomized 1:1:1:1 to sarilumamb 150 or 200 mg every 2 weeks administered by single-use, disposable, prefilled pen or pre-filled syringe. Randomization method was not reported.

Main outcomes measures. The primary endpoint was number of “product technical failures” (PTFs). Patients randomized to the pen were given a diary that had questions related to their ability to remove the cap, start the injection, and complete the injection. Participants were asked to answer the questions each time they used the pen. If the response was “no” to any of the 3 questions, this was considered a “product technical complaint” (PTC). PTCs that had a validated technical cause based on pen evaluation and analysis were considered PTFs.

In addition, patient perceptions and satisfaction with the pen were assessed via questionnaire. At baseline, patients were asked about injections and prior experience with self-injection, and at 12 weeks they were asked about their experiences in using the pen. Other outcomes assessed included adverse events and pharmokinetic parameters.

Results. 217 participants were enrolled: 108 patients were in the pen group (56 randomized to 150 mg and 52 randomized to 200 mg) and 109 were in the syringe group (53 randomized to 150 mg and 56 randomized to 200 mg). Completion rates were similar among groups. Sixteen patients discontinued due to treatment-emergent adverse events. There were no PTFs. There was one PTC, in which the user accidently bumped the pen, which expelled the drug onto the floor.

At baseline, before the first injection, the majority of patients reported that they were not afraid of needles (58%), had past experience with self-injections (55%), and were either “very confident” or “extremely confident” regarding self-injections (55%). After the 12-week assessment phase, when asked about their overall level of satisfaction, 98% of patients reported they were “satisfied” or “very satisfied” with the sarilumab pen.

Treatment emergent adverse events occurred in 66% of patients, with no clinically meaningful differences leading to discontinuation in the pen and syringe groups. The most common adverse events were infections and neutropenia.

Conclusion. Patients successfully completed self-injections with the sarilumab pen and found it easy to use.

Commentary

Rheumatoid arthritis (RA) is a common immune-mediated disease characterized by chronically progressive inflammation and destruction of joints and associated structures, resulting in significant morbidity, mortality, and disability. Improved understanding of RA disease pathogenesis in recent years has led to the development of new biologic treatments designed to target specific elements of the RA inflammatory response.

Sarilumab is an interleukin-6 blocker that was approved in the US in 2017 for the treatment of adult patients with moderately to severely active RA who have had an inadequate response or intolerance to one or more disease-modifying antirheumatic drugs. While a syringe form of this drug is currently available, at the time of this writing the pen has not yet been released.

In this real-world usability study sponsored by Sanofi, there were no technical difficulties with using the pen. Most patients thought the pen was easy or very easy to use, and safety and effeicacy appeared to be generally comparable between the pen and syringe. The pen also offers safety protection features that prevent needlestick injury.

The authors of the current study noted that results from previous studies have shown that patients with RA favor treatment devices that are easy to use, convenient, less painful, and take less time to use, and patients have demonstrated a preference for autoinjector devices over more conventional methods of treatment administration [1–3], such as syringes. Pens have been well accepted for the treatment of other chronic health conditions, including diabetes mellitus, migraine headaches, and growth hormone deficiency, and subcutaneous administration of a tumor necrosis factor (TNF) inhibitor via pen has also been accepted for the treatment of RA [1]. As RA requires lifelong treatment, the use of a pen that is ergonomically designed to take into account the manual dexterity issues relevant to this patient population could potentially enhance compliance.

Applications for Clinical Practice

A prefilled pen was well accepted and associated with favorable patient perceptions, indicating that this delivery system may be a viable option for RA patients who are prescribed sarilumab.

Travel, once reserved for wealthy vacationers and high-level executives, has become a regular experience for many people. The US Travel and Tourism Overview reported that US domestic travel climbed to more than 2.25 billion person-trips in 2017.¹ The US Centers for Disease Control and Prevention (CDC) and the US Travel Association suggest that, based on this frequency and the known rate of diabetes, 17 million people with diabetes travel annually for leisure and 5.6 million for business, and these numbers are expected to increase.²

It stands to reason that as the number of people who travel continues to increase, so too will the number of patients with diabetes seeking medical travel advice. Despite resources available to travelers with diabetes, researchers at the 2016 meeting of the American Diabetes Association noted that only 30% of patients with diabetes who responded to a survey reported being satisfied with the resources available to help them manage their diabetes while traveling.² This article discusses how clinicians can help patients manage their diabetes while traveling, address common travel questions, and prepare patients for emergencies that may arise while traveling.

PRE-TRIP PREPARATION

Provider visit before travel: Checking the bases

Advise patients to schedule an appointment 4 to 6 weeks before their trip.³ At this appointment, give the patient a healthcare provider travel letter (Figure 1) and prescriptions that the patient can hand-carry en route.³ The provider letter should state that the patient has diabetes and should list all supplies the patient needs. The letter should also include specific medications used by the patient and the devices that deliver these medications, eg, Humalog insulin and U-100 syringes⁴ to administer insulin, as well as any food and medication allergies.

Prescriptions should be written for patients to use in the event of an emergency during travel. Prescriptions for diabetes medications should be written with generic names to minimize confusion for those traveling internationally. Additionally, all prescriptions should provide enough medication to last throughout the trip.⁴

Advise patients that rules for filling prescriptions may vary between states and countries.³ Also, the strength of insulin may vary between the United States and other countries. Patients should understand that if they fill their insulin prescription in a foreign country, they may need to purchase new syringes to match the insulin dose. For example, if patients use U-100 syringes and purchase U-40 insulin, they will need to buy U-40 syringes or risk taking too little of a dose.

Remind patients that prescriptions are not necessary for all diabetes supplies but are essential for coverage by insurance companies. Blood glucose testing supplies, ketone strips, and glucose tablets may be purchased in a pharmacy without a prescription. Human insulin may also be purchased over the counter. However, oral medications, glucagon, and analog insulins require a prescription. We suggest that patients who travel have their prescriptions on file at a chain pharmacy rather than an independent one. If they are in the United States, they can go to any branch of the chain pharmacy and easily fill a prescription.

Work with the patient to compile a separate document that details the medication dosing, correction-scale instructions, carbohydrate-to-insulin ratios, and pump settings (basal rates, insulin sensitivity, active insulin time).⁴ Patients who use an insulin pump should record all pump settings in the event that they need to convert to insulin injections during travel.⁴ We suggest that all patients with an insulin pump have an alternate insulin method (eg, pens, vials) and that they carry this with them along with basal insulin in case the pump fails. This level of preparation empowers the patient to assume responsibility for his or her own care if a healthcare provider is not available during travel.

Like all travelers, patients with diabetes should confirm that their immunizations are up to date. Encourage patients to the CDC’s page (wwwnc.cdc.gov/travel) to check the list of vaccines necessary for their region of travel.^4,5 Many special immunizations can be acquired only from a public health department and not from a clinician’s office.

Additionally, depending on the region of travel, prescribing antibiotics or antidiarrheal medications may be necessary to ensure patient safety and comfort. We also recommend that patients with type 1 diabetes obtain a supply of antibiotics and antidiarrheals because they can become sick quickly.

Packing with diabetes: Double is better

The American Diabetes Association recommends that patients pack at least twice the medication and blood-testing supplies they anticipate needing.³ Reinforce to patients the need to pack all medications and supplies in their carry-on bag and to keep this bag in their possession at all times to avoid damage, loss, and extreme changes in temperature and air pressure, which can adversely affect the activity and stability of insulin.

Ask patients about the activities they plan to participate in and how many days they will be traveling, and then recommend shoes that will encourage appropriate foot care.⁴ Patients with diabetes should choose comfort over style when selecting footwear. All new shoes should be purchased and “broken in” 2 to 3 weeks before the trip. Alternating shoes decreases the risk of blisters and calluses.⁴

Emergency abroad: Planning to be prepared

It is crucial to counsel patients on how to respond in an emergency.

Encourage patients with diabetes, especially those who use insulin, to obtain a medical identification bracelet, necklace, or in some cases, a tattoo, that states they use insulin and discloses any allergies.³ This ensures that emergency medical personnel will be aware of the patient’s condition when providing care. Also suggest that your patients have emergency contact information available on their person and their cell phone to expedite assistance in an emergency (Table 2).

Urge patients to determine prior to their departure if their health coverage will change once they leave the state or the country. Some insurance companies require patients to go to a specific healthcare system while others regulate the amount of time a patient can be in the hospital before being transferred home. It is important for patients to be aware of these terms in the event of hospitalization.⁴ Travel insurance should be considered for international travel.

AIRPORT SECURITY: WHAT TO EXPECT WITH DIABETES

The American Diabetes Association works with the US Transportation Security Administration (TSA) to ensure that passengers with diabetes have access to supplies. Travelers with diabetes are allowed to apply for an optional disability notification card, which discreetly informs officers that the passenger has a condition or device that may affect screening procedures.⁶

The TSA suggests that, before going through airport screening, patients with diabetes separate their diabetes supplies from their luggage and declare all items.⁶ Including prescription labels for medications and medical devices helps speed up the security process. Advise patients to carry glucose tablets and other solid foods for treating hypoglycemia when passing through airport security checkpoints.⁷

Since 2016, the TSA has allowed all diabetes-related supplies, medications, and equipment, including liquids and devices, through security after they have been screened by the x-ray scanner or by hand.⁷ People with diabetes are allowed to carry insulin and other liquid medications in amounts greater than 3.4 ounces (100 mLs) through airport security checkpoints.

Insulin can pass safely through x-ray scanners, but if patients are concerned, they may request that their insulin be inspected by hand.⁷ Patients must inform airport security of this decision before the screening process begins. A hand inspection may include swabbing for explosives.

Patients with an insulin pump and a continuous glucose monitoring device may feel uncomfortable during x-ray screening and special security screenings. Remind patients that it is TSA policy that patients do not need to disconnect their devices and can request screening by pat-down rather than x-ray scanner.⁶ It is the responsibility of the patient to research whether the pump can pass through x-ray scanners.

All patients have the right to request a pat-down and can opt out of passing through the x-ray scanner.⁶ However, patients need to inform officers about a pump before screening and must understand that the pump may be subject to further inspection. Usually, this additional inspection includes swabbing the patient’s hands to check for explosive material and a simple pat-down of the insulin pump.⁷

IN-FLIGHT TIPS

Time zones and insulin dosing

Diabetes management is often based on a 24-hour medication schedule. Travel can disrupt this schedule, making it challenging for patients to determine the appropriate medication adjustments. With some assistance, the patient can determine the best course of action based on the direction of travel and the number of time zones crossed.

According to Chandran and Edelman,⁷ medication adjustments are needed only when the patient is traveling east or west, not north or south. As time zones change, day length changes and, consequently, so does the 24-hour regimen many patients follow. As a general rule, traveling east results in a shortened day, requiring a potential reduction in insulin, while traveling west results in a longer day, possibly requiring an increase in insulin dose.⁷ However, this is a guideline and may not be applicable to all patients.⁷

Advise patients to follow local time to administer medications beginning the morning after arrival.⁷ It is not uncommon, due to changes in meal schedules and dosing, for patients to experience hyperglycemia during travel. They should be prepared to correct this if necessary.

Patients using insulin injections should plan to adjust to the new time zone as soon as possible. If the time change is only 1 or 2 hours, they should take their medications before departure according to their normal home time.⁷ Upon arrival, they should resume their insulin regimen based on the local time.

Westward travel. If the patient is traveling west with a time change of 3 or more hours, additional changes may be necessary. Advise patients to take their insulin according to their normal home time before departure. The change in dosing and schedule will depend largely on current glucose control, time of travel, and availability of food and glucose during travel. Encourage patients to discuss these matters with you in advance of any long travel.

Eastward travel. When the patient is traveling east with a time change greater than 3 hours, the day will be consequently shortened. On the day of travel, patients should take their morning dose according to home time. If they are concerned about hypoglycemia, suggest that they decrease the dose by 10%.⁶ On arrival, they should adhere to the new time zone and base insulin dosing on local time.

Advice for insulin pump users. Patients with an insulin pump need make only minimal changes to their dosing schedule. They should continue their routine of basal and bolus doses and change the time on their insulin pump to local time when they arrive. Insulin pump users should bring insulin and syringes as backup; in the event of pump malfunction, the patient should continue to use the same amount of bolus insulin to correct glucose readings and to cover meals.⁷ As for the basal dose, patients can administer a once-daily injection of long-acting insulin, which can be calculated from their pump or accessed from the list they created as part of their pre-travel preparation.⁷

Advice for patients on oral diabetes medications

If a patient is taking an oral medication, it is less crucial to adhere to a time schedule. In fact, in some cases it may be preferable to skip a dose and risk slight hyperglycemia for a few hours rather than take medication too close in time and risk hypoglycemia.⁷

Remind patients to anticipate a change in their oral medication regimen if they travel farther than 5 time zones.⁷ Encourage patients to research time changes and discuss the necessary changes in medication dosage on the day of travel as well as the specific aspects of their trip. A time-zone converter can be found at www.timeanddate.com.⁸

Insulin 101

Storing insulin at the appropriate temperature may be a concern. Insulin should be kept between 40°F and 86°F (4°C–30°C).⁴ Remind patients to carry their insulin with them at all times and to not store it in a car glove compartment or backpack where it can be exposed to excessive sun. The Frio cold pack (ReadyCare, Walnut Creek, CA) is a helpful alternative to refrigeration and can be used to cool insulin when hiking or participating in activities where insulin can overheat. These cooling gel packs are activated when exposed to cold water for 5 to 7 minutes⁵ and are reusable.

Alert patients that insulin names and concentrations may vary among countries. Most insulins are U-100 concentration, which means that for every 1 mL of liquid there are 100 units of insulin. This is the standard insulin concentration used in the United States. There are U-200, U-300, and U-500 insulins as well. In Europe, the standard concentration is U-40 insulin. Syringe sizes are designed to accommodate either U-100 or U-40 insulin. Review these differences with patients and explain the consequences of mixing insulin concentration with syringes of different sizes. Figure 2 shows how to calculate equivalent doses.

Resort tips: Food, drinks, and excursions

A large component of travel is indulging in local cuisine. Patients with diabetes need to be aware of how different foods can affect their diabetes control. Encourage them to research the foods common to the local cuisine. Websites such as Calorie King, MyFitnessPal, Lose it!, and Nutrition Data can help identify the caloric and nutritional makeup of foods.⁹

Advise patients to actively monitor how their blood glucose is affected by new foods by checking blood glucose levels before and after each meal.⁹ Opting for vegetables and protein sources minimizes glucose fluctuations. Remind patients that drinks at resorts may contain more sugar than advertised. Patients should continue to manage their blood glucose by checking levels and by making appropriate insulin adjustments based on the readings. We often advise patients to pack a jar of peanut butter when traveling to ensure a ready source of protein.

Patients who plan to participate in physically challenging activities while travelling should inform all relevant members of the activity staff of their condition. In case of an emergency, hotel staff and guides will be better equipped to help with situations such as hypoglycemia. As noted above, patients should always carry snacks and supplies to treat hypoglycemia in case no alternative food options are available during an excursion. Also, warn patients to avoid walking barefoot. Water shoes are a good alternative to protect feet from cuts and sores.

Patients should inquire about the safety of high-elevation activities. With many glucose meters, every 1,000 feet of elevation results in a 1% to 2% underestimation of blood glucose,¹⁰ which could result in an inaccurate reading. If high-altitude activities are planned, advise patients to bring multiple meters to cross-check glucose readings in cases where inaccuracies (due to elevation) are possible.

Travel, once reserved for wealthy vacationers and high-level executives, has become a regular experience for many people. The US Travel and Tourism Overview reported that US domestic travel climbed to more than 2.25 billion person-trips in 2017.¹ The US Centers for Disease Control and Prevention (CDC) and the US Travel Association suggest that, based on this frequency and the known rate of diabetes, 17 million people with diabetes travel annually for leisure and 5.6 million for business, and these numbers are expected to increase.²

It stands to reason that as the number of people who travel continues to increase, so too will the number of patients with diabetes seeking medical travel advice. Despite resources available to travelers with diabetes, researchers at the 2016 meeting of the American Diabetes Association noted that only 30% of patients with diabetes who responded to a survey reported being satisfied with the resources available to help them manage their diabetes while traveling.² This article discusses how clinicians can help patients manage their diabetes while traveling, address common travel questions, and prepare patients for emergencies that may arise while traveling.

PRE-TRIP PREPARATION

Provider visit before travel: Checking the bases

Advise patients to schedule an appointment 4 to 6 weeks before their trip.³ At this appointment, give the patient a healthcare provider travel letter (Figure 1) and prescriptions that the patient can hand-carry en route.³ The provider letter should state that the patient has diabetes and should list all supplies the patient needs. The letter should also include specific medications used by the patient and the devices that deliver these medications, eg, Humalog insulin and U-100 syringes⁴ to administer insulin, as well as any food and medication allergies.

Prescriptions should be written for patients to use in the event of an emergency during travel. Prescriptions for diabetes medications should be written with generic names to minimize confusion for those traveling internationally. Additionally, all prescriptions should provide enough medication to last throughout the trip.⁴

Advise patients that rules for filling prescriptions may vary between states and countries.³ Also, the strength of insulin may vary between the United States and other countries. Patients should understand that if they fill their insulin prescription in a foreign country, they may need to purchase new syringes to match the insulin dose. For example, if patients use U-100 syringes and purchase U-40 insulin, they will need to buy U-40 syringes or risk taking too little of a dose.

Remind patients that prescriptions are not necessary for all diabetes supplies but are essential for coverage by insurance companies. Blood glucose testing supplies, ketone strips, and glucose tablets may be purchased in a pharmacy without a prescription. Human insulin may also be purchased over the counter. However, oral medications, glucagon, and analog insulins require a prescription. We suggest that patients who travel have their prescriptions on file at a chain pharmacy rather than an independent one. If they are in the United States, they can go to any branch of the chain pharmacy and easily fill a prescription.

Work with the patient to compile a separate document that details the medication dosing, correction-scale instructions, carbohydrate-to-insulin ratios, and pump settings (basal rates, insulin sensitivity, active insulin time).⁴ Patients who use an insulin pump should record all pump settings in the event that they need to convert to insulin injections during travel.⁴ We suggest that all patients with an insulin pump have an alternate insulin method (eg, pens, vials) and that they carry this with them along with basal insulin in case the pump fails. This level of preparation empowers the patient to assume responsibility for his or her own care if a healthcare provider is not available during travel.

Like all travelers, patients with diabetes should confirm that their immunizations are up to date. Encourage patients to the CDC’s page (wwwnc.cdc.gov/travel) to check the list of vaccines necessary for their region of travel.^4,5 Many special immunizations can be acquired only from a public health department and not from a clinician’s office.

Additionally, depending on the region of travel, prescribing antibiotics or antidiarrheal medications may be necessary to ensure patient safety and comfort. We also recommend that patients with type 1 diabetes obtain a supply of antibiotics and antidiarrheals because they can become sick quickly.

Packing with diabetes: Double is better

The American Diabetes Association recommends that patients pack at least twice the medication and blood-testing supplies they anticipate needing.³ Reinforce to patients the need to pack all medications and supplies in their carry-on bag and to keep this bag in their possession at all times to avoid damage, loss, and extreme changes in temperature and air pressure, which can adversely affect the activity and stability of insulin.

Ask patients about the activities they plan to participate in and how many days they will be traveling, and then recommend shoes that will encourage appropriate foot care.⁴ Patients with diabetes should choose comfort over style when selecting footwear. All new shoes should be purchased and “broken in” 2 to 3 weeks before the trip. Alternating shoes decreases the risk of blisters and calluses.⁴

Emergency abroad: Planning to be prepared

It is crucial to counsel patients on how to respond in an emergency.

Encourage patients with diabetes, especially those who use insulin, to obtain a medical identification bracelet, necklace, or in some cases, a tattoo, that states they use insulin and discloses any allergies.³ This ensures that emergency medical personnel will be aware of the patient’s condition when providing care. Also suggest that your patients have emergency contact information available on their person and their cell phone to expedite assistance in an emergency (Table 2).

Urge patients to determine prior to their departure if their health coverage will change once they leave the state or the country. Some insurance companies require patients to go to a specific healthcare system while others regulate the amount of time a patient can be in the hospital before being transferred home. It is important for patients to be aware of these terms in the event of hospitalization.⁴ Travel insurance should be considered for international travel.

AIRPORT SECURITY: WHAT TO EXPECT WITH DIABETES

The American Diabetes Association works with the US Transportation Security Administration (TSA) to ensure that passengers with diabetes have access to supplies. Travelers with diabetes are allowed to apply for an optional disability notification card, which discreetly informs officers that the passenger has a condition or device that may affect screening procedures.⁶

The TSA suggests that, before going through airport screening, patients with diabetes separate their diabetes supplies from their luggage and declare all items.⁶ Including prescription labels for medications and medical devices helps speed up the security process. Advise patients to carry glucose tablets and other solid foods for treating hypoglycemia when passing through airport security checkpoints.⁷

Since 2016, the TSA has allowed all diabetes-related supplies, medications, and equipment, including liquids and devices, through security after they have been screened by the x-ray scanner or by hand.⁷ People with diabetes are allowed to carry insulin and other liquid medications in amounts greater than 3.4 ounces (100 mLs) through airport security checkpoints.

Insulin can pass safely through x-ray scanners, but if patients are concerned, they may request that their insulin be inspected by hand.⁷ Patients must inform airport security of this decision before the screening process begins. A hand inspection may include swabbing for explosives.

Patients with an insulin pump and a continuous glucose monitoring device may feel uncomfortable during x-ray screening and special security screenings. Remind patients that it is TSA policy that patients do not need to disconnect their devices and can request screening by pat-down rather than x-ray scanner.⁶ It is the responsibility of the patient to research whether the pump can pass through x-ray scanners.

All patients have the right to request a pat-down and can opt out of passing through the x-ray scanner.⁶ However, patients need to inform officers about a pump before screening and must understand that the pump may be subject to further inspection. Usually, this additional inspection includes swabbing the patient’s hands to check for explosive material and a simple pat-down of the insulin pump.⁷

IN-FLIGHT TIPS

Time zones and insulin dosing

Diabetes management is often based on a 24-hour medication schedule. Travel can disrupt this schedule, making it challenging for patients to determine the appropriate medication adjustments. With some assistance, the patient can determine the best course of action based on the direction of travel and the number of time zones crossed.

According to Chandran and Edelman,⁷ medication adjustments are needed only when the patient is traveling east or west, not north or south. As time zones change, day length changes and, consequently, so does the 24-hour regimen many patients follow. As a general rule, traveling east results in a shortened day, requiring a potential reduction in insulin, while traveling west results in a longer day, possibly requiring an increase in insulin dose.⁷ However, this is a guideline and may not be applicable to all patients.⁷

Advise patients to follow local time to administer medications beginning the morning after arrival.⁷ It is not uncommon, due to changes in meal schedules and dosing, for patients to experience hyperglycemia during travel. They should be prepared to correct this if necessary.

Patients using insulin injections should plan to adjust to the new time zone as soon as possible. If the time change is only 1 or 2 hours, they should take their medications before departure according to their normal home time.⁷ Upon arrival, they should resume their insulin regimen based on the local time.

Westward travel. If the patient is traveling west with a time change of 3 or more hours, additional changes may be necessary. Advise patients to take their insulin according to their normal home time before departure. The change in dosing and schedule will depend largely on current glucose control, time of travel, and availability of food and glucose during travel. Encourage patients to discuss these matters with you in advance of any long travel.

Eastward travel. When the patient is traveling east with a time change greater than 3 hours, the day will be consequently shortened. On the day of travel, patients should take their morning dose according to home time. If they are concerned about hypoglycemia, suggest that they decrease the dose by 10%.⁶ On arrival, they should adhere to the new time zone and base insulin dosing on local time.

Advice for insulin pump users. Patients with an insulin pump need make only minimal changes to their dosing schedule. They should continue their routine of basal and bolus doses and change the time on their insulin pump to local time when they arrive. Insulin pump users should bring insulin and syringes as backup; in the event of pump malfunction, the patient should continue to use the same amount of bolus insulin to correct glucose readings and to cover meals.⁷ As for the basal dose, patients can administer a once-daily injection of long-acting insulin, which can be calculated from their pump or accessed from the list they created as part of their pre-travel preparation.⁷

Advice for patients on oral diabetes medications

If a patient is taking an oral medication, it is less crucial to adhere to a time schedule. In fact, in some cases it may be preferable to skip a dose and risk slight hyperglycemia for a few hours rather than take medication too close in time and risk hypoglycemia.⁷

Remind patients to anticipate a change in their oral medication regimen if they travel farther than 5 time zones.⁷ Encourage patients to research time changes and discuss the necessary changes in medication dosage on the day of travel as well as the specific aspects of their trip. A time-zone converter can be found at www.timeanddate.com.⁸

Insulin 101

Storing insulin at the appropriate temperature may be a concern. Insulin should be kept between 40°F and 86°F (4°C–30°C).⁴ Remind patients to carry their insulin with them at all times and to not store it in a car glove compartment or backpack where it can be exposed to excessive sun. The Frio cold pack (ReadyCare, Walnut Creek, CA) is a helpful alternative to refrigeration and can be used to cool insulin when hiking or participating in activities where insulin can overheat. These cooling gel packs are activated when exposed to cold water for 5 to 7 minutes⁵ and are reusable.

Alert patients that insulin names and concentrations may vary among countries. Most insulins are U-100 concentration, which means that for every 1 mL of liquid there are 100 units of insulin. This is the standard insulin concentration used in the United States. There are U-200, U-300, and U-500 insulins as well. In Europe, the standard concentration is U-40 insulin. Syringe sizes are designed to accommodate either U-100 or U-40 insulin. Review these differences with patients and explain the consequences of mixing insulin concentration with syringes of different sizes. Figure 2 shows how to calculate equivalent doses.

Resort tips: Food, drinks, and excursions

A large component of travel is indulging in local cuisine. Patients with diabetes need to be aware of how different foods can affect their diabetes control. Encourage them to research the foods common to the local cuisine. Websites such as Calorie King, MyFitnessPal, Lose it!, and Nutrition Data can help identify the caloric and nutritional makeup of foods.⁹

Advise patients to actively monitor how their blood glucose is affected by new foods by checking blood glucose levels before and after each meal.⁹ Opting for vegetables and protein sources minimizes glucose fluctuations. Remind patients that drinks at resorts may contain more sugar than advertised. Patients should continue to manage their blood glucose by checking levels and by making appropriate insulin adjustments based on the readings. We often advise patients to pack a jar of peanut butter when traveling to ensure a ready source of protein.

Patients who plan to participate in physically challenging activities while travelling should inform all relevant members of the activity staff of their condition. In case of an emergency, hotel staff and guides will be better equipped to help with situations such as hypoglycemia. As noted above, patients should always carry snacks and supplies to treat hypoglycemia in case no alternative food options are available during an excursion. Also, warn patients to avoid walking barefoot. Water shoes are a good alternative to protect feet from cuts and sores.

Patients should inquire about the safety of high-elevation activities. With many glucose meters, every 1,000 feet of elevation results in a 1% to 2% underestimation of blood glucose,¹⁰ which could result in an inaccurate reading. If high-altitude activities are planned, advise patients to bring multiple meters to cross-check glucose readings in cases where inaccuracies (due to elevation) are possible.

Travel, once reserved for wealthy vacationers and high-level executives, has become a regular experience for many people. The US Travel and Tourism Overview reported that US domestic travel climbed to more than 2.25 billion person-trips in 2017.¹ The US Centers for Disease Control and Prevention (CDC) and the US Travel Association suggest that, based on this frequency and the known rate of diabetes, 17 million people with diabetes travel annually for leisure and 5.6 million for business, and these numbers are expected to increase.²

It stands to reason that as the number of people who travel continues to increase, so too will the number of patients with diabetes seeking medical travel advice. Despite resources available to travelers with diabetes, researchers at the 2016 meeting of the American Diabetes Association noted that only 30% of patients with diabetes who responded to a survey reported being satisfied with the resources available to help them manage their diabetes while traveling.² This article discusses how clinicians can help patients manage their diabetes while traveling, address common travel questions, and prepare patients for emergencies that may arise while traveling.

PRE-TRIP PREPARATION

Provider visit before travel: Checking the bases

Advise patients to schedule an appointment 4 to 6 weeks before their trip.³ At this appointment, give the patient a healthcare provider travel letter (Figure 1) and prescriptions that the patient can hand-carry en route.³ The provider letter should state that the patient has diabetes and should list all supplies the patient needs. The letter should also include specific medications used by the patient and the devices that deliver these medications, eg, Humalog insulin and U-100 syringes⁴ to administer insulin, as well as any food and medication allergies.

Prescriptions should be written for patients to use in the event of an emergency during travel. Prescriptions for diabetes medications should be written with generic names to minimize confusion for those traveling internationally. Additionally, all prescriptions should provide enough medication to last throughout the trip.⁴

Advise patients that rules for filling prescriptions may vary between states and countries.³ Also, the strength of insulin may vary between the United States and other countries. Patients should understand that if they fill their insulin prescription in a foreign country, they may need to purchase new syringes to match the insulin dose. For example, if patients use U-100 syringes and purchase U-40 insulin, they will need to buy U-40 syringes or risk taking too little of a dose.

Remind patients that prescriptions are not necessary for all diabetes supplies but are essential for coverage by insurance companies. Blood glucose testing supplies, ketone strips, and glucose tablets may be purchased in a pharmacy without a prescription. Human insulin may also be purchased over the counter. However, oral medications, glucagon, and analog insulins require a prescription. We suggest that patients who travel have their prescriptions on file at a chain pharmacy rather than an independent one. If they are in the United States, they can go to any branch of the chain pharmacy and easily fill a prescription.

Work with the patient to compile a separate document that details the medication dosing, correction-scale instructions, carbohydrate-to-insulin ratios, and pump settings (basal rates, insulin sensitivity, active insulin time).⁴ Patients who use an insulin pump should record all pump settings in the event that they need to convert to insulin injections during travel.⁴ We suggest that all patients with an insulin pump have an alternate insulin method (eg, pens, vials) and that they carry this with them along with basal insulin in case the pump fails. This level of preparation empowers the patient to assume responsibility for his or her own care if a healthcare provider is not available during travel.

Like all travelers, patients with diabetes should confirm that their immunizations are up to date. Encourage patients to the CDC’s page (wwwnc.cdc.gov/travel) to check the list of vaccines necessary for their region of travel.^4,5 Many special immunizations can be acquired only from a public health department and not from a clinician’s office.

Additionally, depending on the region of travel, prescribing antibiotics or antidiarrheal medications may be necessary to ensure patient safety and comfort. We also recommend that patients with type 1 diabetes obtain a supply of antibiotics and antidiarrheals because they can become sick quickly.

Packing with diabetes: Double is better

The American Diabetes Association recommends that patients pack at least twice the medication and blood-testing supplies they anticipate needing.³ Reinforce to patients the need to pack all medications and supplies in their carry-on bag and to keep this bag in their possession at all times to avoid damage, loss, and extreme changes in temperature and air pressure, which can adversely affect the activity and stability of insulin.

Ask patients about the activities they plan to participate in and how many days they will be traveling, and then recommend shoes that will encourage appropriate foot care.⁴ Patients with diabetes should choose comfort over style when selecting footwear. All new shoes should be purchased and “broken in” 2 to 3 weeks before the trip. Alternating shoes decreases the risk of blisters and calluses.⁴

Emergency abroad: Planning to be prepared

It is crucial to counsel patients on how to respond in an emergency.

Encourage patients with diabetes, especially those who use insulin, to obtain a medical identification bracelet, necklace, or in some cases, a tattoo, that states they use insulin and discloses any allergies.³ This ensures that emergency medical personnel will be aware of the patient’s condition when providing care. Also suggest that your patients have emergency contact information available on their person and their cell phone to expedite assistance in an emergency (Table 2).

Urge patients to determine prior to their departure if their health coverage will change once they leave the state or the country. Some insurance companies require patients to go to a specific healthcare system while others regulate the amount of time a patient can be in the hospital before being transferred home. It is important for patients to be aware of these terms in the event of hospitalization.⁴ Travel insurance should be considered for international travel.

AIRPORT SECURITY: WHAT TO EXPECT WITH DIABETES

The American Diabetes Association works with the US Transportation Security Administration (TSA) to ensure that passengers with diabetes have access to supplies. Travelers with diabetes are allowed to apply for an optional disability notification card, which discreetly informs officers that the passenger has a condition or device that may affect screening procedures.⁶

The TSA suggests that, before going through airport screening, patients with diabetes separate their diabetes supplies from their luggage and declare all items.⁶ Including prescription labels for medications and medical devices helps speed up the security process. Advise patients to carry glucose tablets and other solid foods for treating hypoglycemia when passing through airport security checkpoints.⁷

Since 2016, the TSA has allowed all diabetes-related supplies, medications, and equipment, including liquids and devices, through security after they have been screened by the x-ray scanner or by hand.⁷ People with diabetes are allowed to carry insulin and other liquid medications in amounts greater than 3.4 ounces (100 mLs) through airport security checkpoints.

Insulin can pass safely through x-ray scanners, but if patients are concerned, they may request that their insulin be inspected by hand.⁷ Patients must inform airport security of this decision before the screening process begins. A hand inspection may include swabbing for explosives.

Patients with an insulin pump and a continuous glucose monitoring device may feel uncomfortable during x-ray screening and special security screenings. Remind patients that it is TSA policy that patients do not need to disconnect their devices and can request screening by pat-down rather than x-ray scanner.⁶ It is the responsibility of the patient to research whether the pump can pass through x-ray scanners.

All patients have the right to request a pat-down and can opt out of passing through the x-ray scanner.⁶ However, patients need to inform officers about a pump before screening and must understand that the pump may be subject to further inspection. Usually, this additional inspection includes swabbing the patient’s hands to check for explosive material and a simple pat-down of the insulin pump.⁷

IN-FLIGHT TIPS

Time zones and insulin dosing

Diabetes management is often based on a 24-hour medication schedule. Travel can disrupt this schedule, making it challenging for patients to determine the appropriate medication adjustments. With some assistance, the patient can determine the best course of action based on the direction of travel and the number of time zones crossed.

According to Chandran and Edelman,⁷ medication adjustments are needed only when the patient is traveling east or west, not north or south. As time zones change, day length changes and, consequently, so does the 24-hour regimen many patients follow. As a general rule, traveling east results in a shortened day, requiring a potential reduction in insulin, while traveling west results in a longer day, possibly requiring an increase in insulin dose.⁷ However, this is a guideline and may not be applicable to all patients.⁷

Advise patients to follow local time to administer medications beginning the morning after arrival.⁷ It is not uncommon, due to changes in meal schedules and dosing, for patients to experience hyperglycemia during travel. They should be prepared to correct this if necessary.

Patients using insulin injections should plan to adjust to the new time zone as soon as possible. If the time change is only 1 or 2 hours, they should take their medications before departure according to their normal home time.⁷ Upon arrival, they should resume their insulin regimen based on the local time.

Westward travel. If the patient is traveling west with a time change of 3 or more hours, additional changes may be necessary. Advise patients to take their insulin according to their normal home time before departure. The change in dosing and schedule will depend largely on current glucose control, time of travel, and availability of food and glucose during travel. Encourage patients to discuss these matters with you in advance of any long travel.

Eastward travel. When the patient is traveling east with a time change greater than 3 hours, the day will be consequently shortened. On the day of travel, patients should take their morning dose according to home time. If they are concerned about hypoglycemia, suggest that they decrease the dose by 10%.⁶ On arrival, they should adhere to the new time zone and base insulin dosing on local time.

Advice for insulin pump users. Patients with an insulin pump need make only minimal changes to their dosing schedule. They should continue their routine of basal and bolus doses and change the time on their insulin pump to local time when they arrive. Insulin pump users should bring insulin and syringes as backup; in the event of pump malfunction, the patient should continue to use the same amount of bolus insulin to correct glucose readings and to cover meals.⁷ As for the basal dose, patients can administer a once-daily injection of long-acting insulin, which can be calculated from their pump or accessed from the list they created as part of their pre-travel preparation.⁷

Advice for patients on oral diabetes medications

If a patient is taking an oral medication, it is less crucial to adhere to a time schedule. In fact, in some cases it may be preferable to skip a dose and risk slight hyperglycemia for a few hours rather than take medication too close in time and risk hypoglycemia.⁷

Remind patients to anticipate a change in their oral medication regimen if they travel farther than 5 time zones.⁷ Encourage patients to research time changes and discuss the necessary changes in medication dosage on the day of travel as well as the specific aspects of their trip. A time-zone converter can be found at www.timeanddate.com.⁸

Insulin 101

Storing insulin at the appropriate temperature may be a concern. Insulin should be kept between 40°F and 86°F (4°C–30°C).⁴ Remind patients to carry their insulin with them at all times and to not store it in a car glove compartment or backpack where it can be exposed to excessive sun. The Frio cold pack (ReadyCare, Walnut Creek, CA) is a helpful alternative to refrigeration and can be used to cool insulin when hiking or participating in activities where insulin can overheat. These cooling gel packs are activated when exposed to cold water for 5 to 7 minutes⁵ and are reusable.

Alert patients that insulin names and concentrations may vary among countries. Most insulins are U-100 concentration, which means that for every 1 mL of liquid there are 100 units of insulin. This is the standard insulin concentration used in the United States. There are U-200, U-300, and U-500 insulins as well. In Europe, the standard concentration is U-40 insulin. Syringe sizes are designed to accommodate either U-100 or U-40 insulin. Review these differences with patients and explain the consequences of mixing insulin concentration with syringes of different sizes. Figure 2 shows how to calculate equivalent doses.

Resort tips: Food, drinks, and excursions

A large component of travel is indulging in local cuisine. Patients with diabetes need to be aware of how different foods can affect their diabetes control. Encourage them to research the foods common to the local cuisine. Websites such as Calorie King, MyFitnessPal, Lose it!, and Nutrition Data can help identify the caloric and nutritional makeup of foods.⁹

Advise patients to actively monitor how their blood glucose is affected by new foods by checking blood glucose levels before and after each meal.⁹ Opting for vegetables and protein sources minimizes glucose fluctuations. Remind patients that drinks at resorts may contain more sugar than advertised. Patients should continue to manage their blood glucose by checking levels and by making appropriate insulin adjustments based on the readings. We often advise patients to pack a jar of peanut butter when traveling to ensure a ready source of protein.

Patients who plan to participate in physically challenging activities while travelling should inform all relevant members of the activity staff of their condition. In case of an emergency, hotel staff and guides will be better equipped to help with situations such as hypoglycemia. As noted above, patients should always carry snacks and supplies to treat hypoglycemia in case no alternative food options are available during an excursion. Also, warn patients to avoid walking barefoot. Water shoes are a good alternative to protect feet from cuts and sores.

Patients should inquire about the safety of high-elevation activities. With many glucose meters, every 1,000 feet of elevation results in a 1% to 2% underestimation of blood glucose,¹⁰ which could result in an inaccurate reading. If high-altitude activities are planned, advise patients to bring multiple meters to cross-check glucose readings in cases where inaccuracies (due to elevation) are possible.

We recommend the following combination treatment:

Normal saline (0.9% NaCl) 1 to 2 L by intravenous (IV) infusion over 2 to 4 hours.  This can be repeated every 6 to 12 hours.

Ketorolac 30-mg IV bolus, which can be repeated every 6 hours. However, patients with coronary artery disease, uncontrolled hypertension, acute renal failure, or cerebrovascular disease should instead receive aceta­minophen 1,000 mg, naproxen sodium 550 mg, or aspirin 325 mg by mouth.

Prochlorperazine or metoclopramide 10-mg IV infusion. This can be repeated every 6 hours. However, to reduce the extrapyramidal adverse effects of these drugs, patients should first receive diphenhydramine 25- to 50-mg IV bolus, which can be repeated every 6 to 8 hours.

Sodium valproate 500 to 1,000 mg by IV infusion over 20 minutes. This can be repeated after 8 hours.

Dexamethasone 4-mg IV bolus every 6 hours, or 10-mg IV bolus once in 24 hours.

Magnesium sulfate 500 to 1,000 mg by IV infusion over 1 hour. This can be repeated every 6 to 12 hours.

If the migraine has not improved after 3 cycles of this regimen, a neurologic consultation should be considered. Other options include dihydroergotamine and occipital nerve blocks¹ performed at the bedside.

GENERAL PRINCIPLES

Managing acute intractable migraine can be frustrating for both the practitioner and the patient. Some general principles are helpful.

Use a combination of drugs. Aborting a severe migraine attack often requires a combination of medications that work synergistically.

Use IV and intramuscular formulations rather than oral formulations: they are more rapidly absorbed, provide faster pain relief, and can be given when the nausea that often accompanies migraine precludes oral treatments.

Rule out secondary causes. The mnemonic SNOOP—systemic signs, neurologic signs, onset, older age, progression of existing headache disorder—is useful for assessing underlying causes.² Any patient presenting with intractable migraine should also have a thorough neuro­logic examination.

Screening electrocardiography may be helpful, as the pretreatment QTc interval may direct the choice of intravenous treatment. If the patient has a prolonged QTc or is taking another drug that could prolong the QTc, certain medications, specifically dopamine receptor antagonists and diphenhydra­mine, should be avoided.

Ask the patient what has worked previously. A particular agent may have been effective in aborting the migraine; thus, a single dose of it could abort the headache, expediting discharge.

Establish if a triptan or ergot derivative has been used during the 24 hours before presentation, as repeated dosing within this interval is not recommended.³

Establish the baseline headache severity. Complete headache relief is difficult to achieve in a patient with chronic daily headache, and establishing a more realistic goal (eg, 50% relief) from the outset is useful.

Antiemetics

Dopamine receptor antagonists are assumed to merely treat nausea in patients with migraine; however, they act independently to abort migraine and thus should be considered, irrespective of the presence of nausea.

The two most commonly used agents are prochlorperazine and metoclopramide. The American Academy of Neurology guidelines recommend prochlorperazine as first-line therapy for acute migraine. Metoclopramide is rated slightly lower and is considered to have moderate benefit.⁴ The Canadian Headache Society cites a high level of evidence supporting prochlorperazine and a moderate level of evidence supporting metoclopramide.⁵ The American Headache Society assessment of parenteral pharmacotherapies gives prochlorperazine and metoclopramide a level B recommendation of “should offer” (a recommendation only additionally assigned to subcutaneous sumatriptan).³ Hence, either agent can be used.

To reduce the risk of posttreatment akathisia, diphenhydramine or benztropine may be given before starting a dopamine receptor antagonist. Diphenhydramine may be independently effective in migraine treatment,^6,7 but  data on this are limited.

Ketorolac, ibuprofen

Ketorolac and ibuprofen are the only available nonsteroidal antiinflammatory drugs (NSAIDs) for IV administration. The Canadian Headache Society guidelines strongly recommend ketorolac for the treatment of migraine in emergency settings.⁵ Doses range from 30 mg to 60 mg.¹ Ibuprofen 400 to 800 mg by IV infusion is an acceptable alternative. These medications should be avoided in patients with renal failure or severe coronary artery disease.

Oral naproxen sodium is a possible alternative in patients with cardiovascular disease, as it has been shown to carry a lower cardiovascular risk than other NSAIDs.⁸

The same concerns in patients with renal dysfunction apply to any NSAID, as the enzyme cyclooxygenase plays a constitutive role in glomerular function.

Antiepileptic drugs

The antiepileptic drugs sodium valproate and levetiracetam are available in IV formulations that have demonstrated efficacy in the treatment of status migrainosus¹ (ie, migraine lasting more than 72 hours). Valproate has the strongest track record, is well tolerated, and is effective in rapidly aborting migraine.⁹

Volume repletion

Although its use is anecdotal and to date no trial has measured its efficacy, IV volume repletion is often used in acute migraine, as most headache experts surmise it to be highly effective, especially in patients with prolonged nausea or vomiting.¹

Magnesium

IV magnesium is effective, particularly for migraine with aura.¹⁰ Hypotension is a common side effect, and pretreatment or concurrent treatment with IV fluids is advised. Doses from 500 mg to 1,000 mg have demonstrated efficacy.¹⁰

Corticosteroids

Corticosteroids can be used in the treatment of status migrainosus. Most studies have shown benefit in preventing recurrences rather than merely aborting migraine.¹¹ A systematic review suggested that recurrent headaches are milder with corticosteroid treatment; 19 of 25 studies indicated favorable benefit, and 6 of 19 studies indicated noninferior outcomes.¹²

Both IV methylprednisolone and IV dexamethasone may be considered.¹² Dexamethasone appears to be particularly effective in preventing headache recurrence when combined with other IV therapies.¹³ It can be given as a single dose of 10 mg, or as repeated doses of 4 mg up to 16 mg/day.¹ Patients with active psychosis or uncontrolled diabetes should be closely monitored for these conditions, which corticosteroids can worsen.

Serotoninergic agents

Serotonin agonists including subcutaneous sumatriptan and IV dihydroergotamine are highly effective, with proven statistical and clinical benefit.⁴ They should be considered in patients with no known history of coronary artery disease or other vaso-occlusive vascular disorder.¹

Ideally, IV dihydroergotamine should be administered after consultation with a neurologist or headache specialist, given the pretreatment and cotreatment requirements often necessary to suppress its side effects. Careful titration is important to prevent transient headache exacerbations during infusion, as well as abdominal cramping, nausea, and diarrhea.

Avoid opioids

Opioids should be avoided. Evidence supporting their use in acute migraine is extremely limited,³ and the risks of migraine becoming chronic and of addiction are high.¹⁴ Safer, more effective alternatives have been detailed above.

A detailed algorithm for the management of patients with acute migraine has been published¹⁴ and is aimed at decreasing acute treatment with opioids and barbiturates.

We recommend the following combination treatment:

Normal saline (0.9% NaCl) 1 to 2 L by intravenous (IV) infusion over 2 to 4 hours.  This can be repeated every 6 to 12 hours.

Ketorolac 30-mg IV bolus, which can be repeated every 6 hours. However, patients with coronary artery disease, uncontrolled hypertension, acute renal failure, or cerebrovascular disease should instead receive aceta­minophen 1,000 mg, naproxen sodium 550 mg, or aspirin 325 mg by mouth.

Prochlorperazine or metoclopramide 10-mg IV infusion. This can be repeated every 6 hours. However, to reduce the extrapyramidal adverse effects of these drugs, patients should first receive diphenhydramine 25- to 50-mg IV bolus, which can be repeated every 6 to 8 hours.

Sodium valproate 500 to 1,000 mg by IV infusion over 20 minutes. This can be repeated after 8 hours.

Dexamethasone 4-mg IV bolus every 6 hours, or 10-mg IV bolus once in 24 hours.

Magnesium sulfate 500 to 1,000 mg by IV infusion over 1 hour. This can be repeated every 6 to 12 hours.

If the migraine has not improved after 3 cycles of this regimen, a neurologic consultation should be considered. Other options include dihydroergotamine and occipital nerve blocks¹ performed at the bedside.

GENERAL PRINCIPLES

Managing acute intractable migraine can be frustrating for both the practitioner and the patient. Some general principles are helpful.

Use a combination of drugs. Aborting a severe migraine attack often requires a combination of medications that work synergistically.

Use IV and intramuscular formulations rather than oral formulations: they are more rapidly absorbed, provide faster pain relief, and can be given when the nausea that often accompanies migraine precludes oral treatments.

Rule out secondary causes. The mnemonic SNOOP—systemic signs, neurologic signs, onset, older age, progression of existing headache disorder—is useful for assessing underlying causes.² Any patient presenting with intractable migraine should also have a thorough neuro­logic examination.

Screening electrocardiography may be helpful, as the pretreatment QTc interval may direct the choice of intravenous treatment. If the patient has a prolonged QTc or is taking another drug that could prolong the QTc, certain medications, specifically dopamine receptor antagonists and diphenhydra­mine, should be avoided.

Ask the patient what has worked previously. A particular agent may have been effective in aborting the migraine; thus, a single dose of it could abort the headache, expediting discharge.

Establish if a triptan or ergot derivative has been used during the 24 hours before presentation, as repeated dosing within this interval is not recommended.³

Establish the baseline headache severity. Complete headache relief is difficult to achieve in a patient with chronic daily headache, and establishing a more realistic goal (eg, 50% relief) from the outset is useful.

Antiemetics

Dopamine receptor antagonists are assumed to merely treat nausea in patients with migraine; however, they act independently to abort migraine and thus should be considered, irrespective of the presence of nausea.

The two most commonly used agents are prochlorperazine and metoclopramide. The American Academy of Neurology guidelines recommend prochlorperazine as first-line therapy for acute migraine. Metoclopramide is rated slightly lower and is considered to have moderate benefit.⁴ The Canadian Headache Society cites a high level of evidence supporting prochlorperazine and a moderate level of evidence supporting metoclopramide.⁵ The American Headache Society assessment of parenteral pharmacotherapies gives prochlorperazine and metoclopramide a level B recommendation of “should offer” (a recommendation only additionally assigned to subcutaneous sumatriptan).³ Hence, either agent can be used.

To reduce the risk of posttreatment akathisia, diphenhydramine or benztropine may be given before starting a dopamine receptor antagonist. Diphenhydramine may be independently effective in migraine treatment,^6,7 but  data on this are limited.

Ketorolac, ibuprofen

Ketorolac and ibuprofen are the only available nonsteroidal antiinflammatory drugs (NSAIDs) for IV administration. The Canadian Headache Society guidelines strongly recommend ketorolac for the treatment of migraine in emergency settings.⁵ Doses range from 30 mg to 60 mg.¹ Ibuprofen 400 to 800 mg by IV infusion is an acceptable alternative. These medications should be avoided in patients with renal failure or severe coronary artery disease.

Oral naproxen sodium is a possible alternative in patients with cardiovascular disease, as it has been shown to carry a lower cardiovascular risk than other NSAIDs.⁸

The same concerns in patients with renal dysfunction apply to any NSAID, as the enzyme cyclooxygenase plays a constitutive role in glomerular function.

Antiepileptic drugs

The antiepileptic drugs sodium valproate and levetiracetam are available in IV formulations that have demonstrated efficacy in the treatment of status migrainosus¹ (ie, migraine lasting more than 72 hours). Valproate has the strongest track record, is well tolerated, and is effective in rapidly aborting migraine.⁹

Volume repletion

Although its use is anecdotal and to date no trial has measured its efficacy, IV volume repletion is often used in acute migraine, as most headache experts surmise it to be highly effective, especially in patients with prolonged nausea or vomiting.¹

Magnesium

IV magnesium is effective, particularly for migraine with aura.¹⁰ Hypotension is a common side effect, and pretreatment or concurrent treatment with IV fluids is advised. Doses from 500 mg to 1,000 mg have demonstrated efficacy.¹⁰

Corticosteroids

Corticosteroids can be used in the treatment of status migrainosus. Most studies have shown benefit in preventing recurrences rather than merely aborting migraine.¹¹ A systematic review suggested that recurrent headaches are milder with corticosteroid treatment; 19 of 25 studies indicated favorable benefit, and 6 of 19 studies indicated noninferior outcomes.¹²

Both IV methylprednisolone and IV dexamethasone may be considered.¹² Dexamethasone appears to be particularly effective in preventing headache recurrence when combined with other IV therapies.¹³ It can be given as a single dose of 10 mg, or as repeated doses of 4 mg up to 16 mg/day.¹ Patients with active psychosis or uncontrolled diabetes should be closely monitored for these conditions, which corticosteroids can worsen.

Serotoninergic agents

Serotonin agonists including subcutaneous sumatriptan and IV dihydroergotamine are highly effective, with proven statistical and clinical benefit.⁴ They should be considered in patients with no known history of coronary artery disease or other vaso-occlusive vascular disorder.¹

Ideally, IV dihydroergotamine should be administered after consultation with a neurologist or headache specialist, given the pretreatment and cotreatment requirements often necessary to suppress its side effects. Careful titration is important to prevent transient headache exacerbations during infusion, as well as abdominal cramping, nausea, and diarrhea.

Avoid opioids

Opioids should be avoided. Evidence supporting their use in acute migraine is extremely limited,³ and the risks of migraine becoming chronic and of addiction are high.¹⁴ Safer, more effective alternatives have been detailed above.

A detailed algorithm for the management of patients with acute migraine has been published¹⁴ and is aimed at decreasing acute treatment with opioids and barbiturates.

We recommend the following combination treatment:

Normal saline (0.9% NaCl) 1 to 2 L by intravenous (IV) infusion over 2 to 4 hours.  This can be repeated every 6 to 12 hours.

Ketorolac 30-mg IV bolus, which can be repeated every 6 hours. However, patients with coronary artery disease, uncontrolled hypertension, acute renal failure, or cerebrovascular disease should instead receive aceta­minophen 1,000 mg, naproxen sodium 550 mg, or aspirin 325 mg by mouth.

Prochlorperazine or metoclopramide 10-mg IV infusion. This can be repeated every 6 hours. However, to reduce the extrapyramidal adverse effects of these drugs, patients should first receive diphenhydramine 25- to 50-mg IV bolus, which can be repeated every 6 to 8 hours.

Sodium valproate 500 to 1,000 mg by IV infusion over 20 minutes. This can be repeated after 8 hours.

Dexamethasone 4-mg IV bolus every 6 hours, or 10-mg IV bolus once in 24 hours.

Magnesium sulfate 500 to 1,000 mg by IV infusion over 1 hour. This can be repeated every 6 to 12 hours.

If the migraine has not improved after 3 cycles of this regimen, a neurologic consultation should be considered. Other options include dihydroergotamine and occipital nerve blocks¹ performed at the bedside.

GENERAL PRINCIPLES

Managing acute intractable migraine can be frustrating for both the practitioner and the patient. Some general principles are helpful.

Use a combination of drugs. Aborting a severe migraine attack often requires a combination of medications that work synergistically.

Use IV and intramuscular formulations rather than oral formulations: they are more rapidly absorbed, provide faster pain relief, and can be given when the nausea that often accompanies migraine precludes oral treatments.

Rule out secondary causes. The mnemonic SNOOP—systemic signs, neurologic signs, onset, older age, progression of existing headache disorder—is useful for assessing underlying causes.² Any patient presenting with intractable migraine should also have a thorough neuro­logic examination.

Screening electrocardiography may be helpful, as the pretreatment QTc interval may direct the choice of intravenous treatment. If the patient has a prolonged QTc or is taking another drug that could prolong the QTc, certain medications, specifically dopamine receptor antagonists and diphenhydra­mine, should be avoided.

Ask the patient what has worked previously. A particular agent may have been effective in aborting the migraine; thus, a single dose of it could abort the headache, expediting discharge.

Establish if a triptan or ergot derivative has been used during the 24 hours before presentation, as repeated dosing within this interval is not recommended.³

Establish the baseline headache severity. Complete headache relief is difficult to achieve in a patient with chronic daily headache, and establishing a more realistic goal (eg, 50% relief) from the outset is useful.

Antiemetics

Dopamine receptor antagonists are assumed to merely treat nausea in patients with migraine; however, they act independently to abort migraine and thus should be considered, irrespective of the presence of nausea.

The two most commonly used agents are prochlorperazine and metoclopramide. The American Academy of Neurology guidelines recommend prochlorperazine as first-line therapy for acute migraine. Metoclopramide is rated slightly lower and is considered to have moderate benefit.⁴ The Canadian Headache Society cites a high level of evidence supporting prochlorperazine and a moderate level of evidence supporting metoclopramide.⁵ The American Headache Society assessment of parenteral pharmacotherapies gives prochlorperazine and metoclopramide a level B recommendation of “should offer” (a recommendation only additionally assigned to subcutaneous sumatriptan).³ Hence, either agent can be used.

To reduce the risk of posttreatment akathisia, diphenhydramine or benztropine may be given before starting a dopamine receptor antagonist. Diphenhydramine may be independently effective in migraine treatment,^6,7 but  data on this are limited.

Ketorolac, ibuprofen

Ketorolac and ibuprofen are the only available nonsteroidal antiinflammatory drugs (NSAIDs) for IV administration. The Canadian Headache Society guidelines strongly recommend ketorolac for the treatment of migraine in emergency settings.⁵ Doses range from 30 mg to 60 mg.¹ Ibuprofen 400 to 800 mg by IV infusion is an acceptable alternative. These medications should be avoided in patients with renal failure or severe coronary artery disease.

Oral naproxen sodium is a possible alternative in patients with cardiovascular disease, as it has been shown to carry a lower cardiovascular risk than other NSAIDs.⁸

The same concerns in patients with renal dysfunction apply to any NSAID, as the enzyme cyclooxygenase plays a constitutive role in glomerular function.

Antiepileptic drugs

The antiepileptic drugs sodium valproate and levetiracetam are available in IV formulations that have demonstrated efficacy in the treatment of status migrainosus¹ (ie, migraine lasting more than 72 hours). Valproate has the strongest track record, is well tolerated, and is effective in rapidly aborting migraine.⁹

Volume repletion

Although its use is anecdotal and to date no trial has measured its efficacy, IV volume repletion is often used in acute migraine, as most headache experts surmise it to be highly effective, especially in patients with prolonged nausea or vomiting.¹

Magnesium

IV magnesium is effective, particularly for migraine with aura.¹⁰ Hypotension is a common side effect, and pretreatment or concurrent treatment with IV fluids is advised. Doses from 500 mg to 1,000 mg have demonstrated efficacy.¹⁰

Corticosteroids

Corticosteroids can be used in the treatment of status migrainosus. Most studies have shown benefit in preventing recurrences rather than merely aborting migraine.¹¹ A systematic review suggested that recurrent headaches are milder with corticosteroid treatment; 19 of 25 studies indicated favorable benefit, and 6 of 19 studies indicated noninferior outcomes.¹²

Both IV methylprednisolone and IV dexamethasone may be considered.¹² Dexamethasone appears to be particularly effective in preventing headache recurrence when combined with other IV therapies.¹³ It can be given as a single dose of 10 mg, or as repeated doses of 4 mg up to 16 mg/day.¹ Patients with active psychosis or uncontrolled diabetes should be closely monitored for these conditions, which corticosteroids can worsen.

Serotoninergic agents

Serotonin agonists including subcutaneous sumatriptan and IV dihydroergotamine are highly effective, with proven statistical and clinical benefit.⁴ They should be considered in patients with no known history of coronary artery disease or other vaso-occlusive vascular disorder.¹

Ideally, IV dihydroergotamine should be administered after consultation with a neurologist or headache specialist, given the pretreatment and cotreatment requirements often necessary to suppress its side effects. Careful titration is important to prevent transient headache exacerbations during infusion, as well as abdominal cramping, nausea, and diarrhea.

Avoid opioids

Opioids should be avoided. Evidence supporting their use in acute migraine is extremely limited,³ and the risks of migraine becoming chronic and of addiction are high.¹⁴ Safer, more effective alternatives have been detailed above.

A detailed algorithm for the management of patients with acute migraine has been published¹⁴ and is aimed at decreasing acute treatment with opioids and barbiturates.

The Trump administration seeks to reorganize several federal agencies as part of a sweeping reform proposal, issued June 21.

“Government in the 21st century is fundamentally a services business, and modern information technology should be at the heart of the U.S. government service delivery model,” according to the administration’s reform proposal. “And yet, today’s Executive branch is still aligned to the stove-piped organizational constructs of the 20th century, which in many cases have grown inefficient and out of date. Consequently, the public and our workforce are frustrated with government’s ability to deliver its mission in an effective, efficient, and secure way.”

tupungato/Thinkstock

Under the proposal, nutrition assistance programs currently run out of the U.S. Department of Agriculture (USDA) including the Supplemental Nutrition Assistance Program (SNAP) and the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) would move to the Department of Health and Human Services, which would be rebranded the Department of Health and Public Welfare.

Moving these programs “would allow for better and easier coordination across programs that serve similar populations, ensuring consistent policies and a single point of administration for the major public assistance programs,” according to the proposal. “This single point of administration would lead to reduced duplication in state reporting requirements and other administrative burdens, and a more streamlined process for issuing guidance, writing regulations, and approving waivers.”

Food oversight functions would move from the Food and Drug Administration to the USDA; FDA would be rebranded the Federal Drug Administration and focus on drugs, devices, biologics, tobacco, dietary supplements, and cosmetics.

The administration also proposed to created a Council on Public Assistance comprised of “all federal agencies that administer public benefits, with a statutory authority to set cross-cutting program policies, including uniform work requirements.”

Other functions of the council would include approving service plans and waivers by states under Welfare-to-Work projects; resolving disputes when multiple agencies disagree on a particular policy; and recommending policy changes to eliminate barriers at the federal, state, and local level to getting welfare beneficiaries to work.

The proposal also calls for a restructuring of the National Institutes of Health “to ensure operations are effective and efficient,” with no detail provided. It would also place the Agency for Healthcare Research and Quality under the auspices of NIH.

The Strategic National Stockpile would be managed by the Assistant Secretary for Preparedness and Response “to consolidate strategic decision making around the development and procurement of medical countermeasures, and streamline operational decisions during responses to public health and other emergencies to improve responsiveness.”

[email protected]

The Trump administration seeks to reorganize several federal agencies as part of a sweeping reform proposal, issued June 21.

“Government in the 21st century is fundamentally a services business, and modern information technology should be at the heart of the U.S. government service delivery model,” according to the administration’s reform proposal. “And yet, today’s Executive branch is still aligned to the stove-piped organizational constructs of the 20th century, which in many cases have grown inefficient and out of date. Consequently, the public and our workforce are frustrated with government’s ability to deliver its mission in an effective, efficient, and secure way.”

tupungato/Thinkstock

Under the proposal, nutrition assistance programs currently run out of the U.S. Department of Agriculture (USDA) including the Supplemental Nutrition Assistance Program (SNAP) and the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) would move to the Department of Health and Human Services, which would be rebranded the Department of Health and Public Welfare.

Moving these programs “would allow for better and easier coordination across programs that serve similar populations, ensuring consistent policies and a single point of administration for the major public assistance programs,” according to the proposal. “This single point of administration would lead to reduced duplication in state reporting requirements and other administrative burdens, and a more streamlined process for issuing guidance, writing regulations, and approving waivers.”

Food oversight functions would move from the Food and Drug Administration to the USDA; FDA would be rebranded the Federal Drug Administration and focus on drugs, devices, biologics, tobacco, dietary supplements, and cosmetics.

The administration also proposed to created a Council on Public Assistance comprised of “all federal agencies that administer public benefits, with a statutory authority to set cross-cutting program policies, including uniform work requirements.”

Other functions of the council would include approving service plans and waivers by states under Welfare-to-Work projects; resolving disputes when multiple agencies disagree on a particular policy; and recommending policy changes to eliminate barriers at the federal, state, and local level to getting welfare beneficiaries to work.

The proposal also calls for a restructuring of the National Institutes of Health “to ensure operations are effective and efficient,” with no detail provided. It would also place the Agency for Healthcare Research and Quality under the auspices of NIH.

The Strategic National Stockpile would be managed by the Assistant Secretary for Preparedness and Response “to consolidate strategic decision making around the development and procurement of medical countermeasures, and streamline operational decisions during responses to public health and other emergencies to improve responsiveness.”

[email protected]

The Trump administration seeks to reorganize several federal agencies as part of a sweeping reform proposal, issued June 21.

“Government in the 21st century is fundamentally a services business, and modern information technology should be at the heart of the U.S. government service delivery model,” according to the administration’s reform proposal. “And yet, today’s Executive branch is still aligned to the stove-piped organizational constructs of the 20th century, which in many cases have grown inefficient and out of date. Consequently, the public and our workforce are frustrated with government’s ability to deliver its mission in an effective, efficient, and secure way.”

tupungato/Thinkstock

Under the proposal, nutrition assistance programs currently run out of the U.S. Department of Agriculture (USDA) including the Supplemental Nutrition Assistance Program (SNAP) and the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) would move to the Department of Health and Human Services, which would be rebranded the Department of Health and Public Welfare.

Moving these programs “would allow for better and easier coordination across programs that serve similar populations, ensuring consistent policies and a single point of administration for the major public assistance programs,” according to the proposal. “This single point of administration would lead to reduced duplication in state reporting requirements and other administrative burdens, and a more streamlined process for issuing guidance, writing regulations, and approving waivers.”

Food oversight functions would move from the Food and Drug Administration to the USDA; FDA would be rebranded the Federal Drug Administration and focus on drugs, devices, biologics, tobacco, dietary supplements, and cosmetics.

The administration also proposed to created a Council on Public Assistance comprised of “all federal agencies that administer public benefits, with a statutory authority to set cross-cutting program policies, including uniform work requirements.”

Other functions of the council would include approving service plans and waivers by states under Welfare-to-Work projects; resolving disputes when multiple agencies disagree on a particular policy; and recommending policy changes to eliminate barriers at the federal, state, and local level to getting welfare beneficiaries to work.

The proposal also calls for a restructuring of the National Institutes of Health “to ensure operations are effective and efficient,” with no detail provided. It would also place the Agency for Healthcare Research and Quality under the auspices of NIH.

The Strategic National Stockpile would be managed by the Assistant Secretary for Preparedness and Response “to consolidate strategic decision making around the development and procurement of medical countermeasures, and streamline operational decisions during responses to public health and other emergencies to improve responsiveness.”

[email protected]

A 29-year-old African American woman presents with a photosensitive malar rash, fatigue, morning stiffness, and swelling in her hands. She is found to have elevated anti­nuclear antibody at a titer of 1:320. A complete blood cell count demonstrates leukopenia and thrombocytopenia. Results of renal function testing and urinalysis are within normal limits. She has no other medical problems and no history of blood clots or pregnancy loss.

Her arthritis and rash suggest systemic lupus erythematosus. She is counseled to avoid sun exposure, and treatment with hydroxychloroquine is considered.

WHAT IS HYDROXYCHLOROQUINE?

Hydroxychloroquine was developed to treat malaria but was later found to have immunomodulatory properties. It is now approved by the US Food and Drug Administration for treatment of discoid lupus, systemic lupus ery­thematosus, and rheumatoid arthritis. It is also approved to treat malaria; however, of the several malarial parasites, only Plasmodium falciparum can still be cured by hydroxychloroquine, and growing resistance limits the geographic locations where this drug can be used effectively.^1,2

HISTORICAL BACKGROUND

Antimalarial drugs were discovered shortly before World War II. Their production was industrialized during the war because malaria was a leading cause of disease among soldiers, especially those deployed to the South Pacific.³

Atabrine (quinacrine), the first antimalarial widely used, had numerous side effects including yellowing of the skin. Aggressive research efforts to develop an alternative led to field testing of one of its derivative compounds, chloroquine, by the US Army in 1943. Continued chemical modification would create hydroxychloroquine, introduced in 1955.

A serendipitous consequence of the mass use of antimalarials during World War II was the discovery that they could be used to treat inflammatory arthritis and lupus. Eight years after the war ended, Shee⁴ reported that chloroquine had a beneficial effect on lupus and rheumatoid arthritis in US soldiers. Hydroxychloroquine is now the most commonly prescribed antimalarial for treatment of autoimmune disease.

HOW HYDROXYCHLOROQUINE WORKS

The primary mechanism by which hydroxychloroquine modulates systemic lupus erythematosus is by suppressing activation of Toll-like receptors, which exist on the surface of endosomes and play a significant role in the innate immune response and in autoimmune disease. Their activation is necessary for the expression of interferon-regulated genes and production of tumor necrosis factor alpha, which are key in the cell-mediated inflammatory response.

Antimalarial drugs such as hydroxychlor­oquine prevent Toll-like receptor activation by binding directly to nucleic acids in the activation pathway.⁵ In vitro studies show that blocking this pathway blunts the body’s primary cell-mediated inflammatory response; in vivo studies show that use of hydroxychloroquine is strongly correlated with a reduction in interferon alpha levels.⁶ The powerful effect of hydroxychloroquine on the cell-mediated pattern of inflammation found in lupus is consistent with this theory.

It was previously hypothesized that the immune-modulating effects of hydroxychloroquine were associated with a more general dysregulation of cellular lysosomes through inhibition of proteolysis or changes in cellular pH.⁷ This theory has since been displaced by the more specific and elegant mechanism described above.⁵

HOW WELL DOES IT WORK?

Benefit in systemic lupus erythematosus

Hydroxychloroquine has consistently demonstrated significant and multifaceted benefit in patients with systemic lupus erythematosus.

A systematic review of 95 articles⁸ concluded that this drug decreases lupus flares and decreases mortality rates in lupus patients by at least 50%, with a high level of evidence. Beneficial effects that had a moderate level of evidence were an increase in bone mineral density, fewer thrombotic events, and fewer cases of irreversible organ damage.

The preventive effect of hydroxychlor­oquine on thrombosis in lupus patients has been consistently demonstrated and is one of the key reasons the drug is considered a cornerstone of therapy in this disease.⁹ A nested case-control study of patients with lupus and thromboembolism demonstrated an odds ratio of 0.31 and relative risk reduction of 68% for those using antimalarials.¹⁰

Benefit in antiphospholipid antibody syndrome

Hydroxychloroquine prevents thrombosis in other diseases as well. For example, it has been shown to reduce the incidence of thrombotic events in patients with primary antiphospholipid syndrome.

In a retrospective cohort study in 114 patients with this disease, hydroxychloroquine significantly reduced the incidence of arterial thrombotic events over 10 years of follow-up (recurrence incidence 0 in those treated with hydroxychloroquine vs 1.14% in those not treated).¹¹ The study also tracked levels of antiphospholipid antibodies and reported that hydroxychloroquine significantly reduced the levels of antibodies to cardiolipin and beta-2 glycoprotein 1, both implicated in the pathology of thrombosis.¹¹

In vitro studies have also demonstrated that hydroxychloroquine can modulate a dysregulated inflammatory system to reduce thrombosis. For example, it has been shown that hydroxychloroquine can reverse platelet activation by antiphospholipid antibodies, prevent linking of antibody complexes to cell membranes, and promote proper membrane protein expression, thereby reducing the thrombotic qualities of antiphospholipid antibodies and even improving clearance times of antiphospholipid-related thrombi.¹²

Though there is less evidence, hydroxychloroquine has also shown benefit in rheumatoid arthritis, where it can be used by itself in mild disease or as part of combination therapy with active arthritis. Compared with biologic therapy in patients with early aggressive rheumatoid arthritis, triple therapy with methotrexate, sulfasalazine, and hydroxychloroquine was nearly as effective in terms of quality of life, and it cost only one-third as much, saving $20,000 per year of therapy per patient.¹³

Hydroxychloroquine has also been compared directly with chloroquine, its closest relation, in a large study incorporating patients with rheumatoid arthritis and patients with systemic lupus erythematosus. Patients using chloroquine experienced significantly more side effects, though it did prove marginally more effective.¹⁴

No benefit shown in Sjögren syndrome

Unfortunately, despite widespread use, hydroxychloroquine has not demonstrated positive clinical effects when used to treat primary Sjögren syndrome. Most notably, a 2014 randomized controlled trial of hydroxychloroquine vs placebo in 120 Sjögren patients found no significant improvement in primary symptoms of dryness, pain, or fatigue after 6 months of therapy.¹⁵

Metabolic benefits

Unexpectedly, hydroxychloroquine is associated with multiple metabolic benefits including improved lipid profiles and lower blood glucose levels. These findings, in addition to a reduced incidence of thrombosis, were initially reported in the Baltimore Lupus Cohort in 1996.¹⁶ Specifically, longitudinal evaluation of a cohort of lupus patients showed that hydroxychloroquine use was associated with a 7.6% reduction in total cholesterol and a 13.7% reduction in low-density lipoprotein cholesterol (LDL-C) over 3 months of therapy.¹⁷

Similar findings, including a reduction in LDL-C and an increase in high-density lipoprotein cholesterol, were strongly associated with the addition of hydroxychloroquine to methotrexate or to methotrexate and etanercept in a large cohort of rheumatoid arthritis patients followed over 2 years of therapy.¹⁸

In nondiabetic women with systemic lupus erythematosus or rheumatoid arthritis, average blood glucose was significantly lower in those taking hydroxychloroquine than in nonusers. The incidence of insulin resistance was also lower, but the difference was not statistically significant.¹⁹

Some have suggested that hydroxychloroquine may prevent diabetes mellitus. In a retrospective case series, compared with rheumatoid arthritis patients not taking the drug, patients treated with hydroxychloroquine for more than 4 years had a 25% lower risk of developing diabetes mellitus.²⁰

In view of these metabolic benefits, especially regarding lipid regulation, and the above described antithrombotic properties of hydroxychloroquine, some researchers have recently hypothesized that hydroxychloroquine may be of benefit in patients with coronary artery disease.²¹ They suggested that the inflammatory contribution to the mechanism of coronary artery disease could be lessened by hydroxychloroquine even in patients without lupus erythematosus or rheumatoid arthritis.

PHARMACOLOGIC PROPERTIES

Understanding the pharmacologic properties of hydroxychloroquine is key to using it appropriately in clinical practice.

The half-life of elimination of hydroxychloroquine is 40 to 50 days, with half of the drug excreted renally in a concentration-dependent fashion.^22,23 The drug reaches 95% of its steady-state concentration by about 6 months of therapy. Shorter durations of therapy do not provide adequate time for the drug to achieve steady-state concentration and may not allow patients and providers time to see its full clinical results. Therefore, its manufacturers recommend a 6-month trial of therapy to adequately determine if the drug improves symptoms.¹

The oral bioavailability of hydroxychloroquine is about 75%, but pharmacokinetics vary among individuals.^22,23 It has been suggested that this variability affects the efficacy of hydroxychloroquine. In a study of 300 patients with cutaneous lupus erythematosus, those whose treatment failed had significantly lower blood concentrations of hydroxychloroquine, while those who achieved complete remission had significantly higher concentrations.²⁴

Another study found that titrating doses to target therapeutic blood concentrations can reduce disease activity in cutaneous lupus erythematosus.²⁵ Measuring the blood concentration of hydroxychloroquine is not common in clinical practice but may have a role in select patients in whom initial therapy using a standard dosing regimen does not produce the desired results.

HOW SAFE IS HYDROXYCHLOROQUINE?

Hydroxychloroquine has numerous adverse effects, necessitating vigilance on the part of the prescriber. Most commonly reported are retinopathy, hyperpigmentation, myopathy, and skin reactions.¹

Retinopathy

Retinopathy’s irreversibility—the threat of permanent vision loss—and its substantial prevalence in patients with a large drug exposure history, have marked retinopathy as the most concerning potential toxicity. The risk of ocular toxicity increases with the cumulative hydroxychloroquine dose. The prevalence of retinopathy in those using the drug less than 10 years is less than 2%; in contrast, the prevalence in patients with more than 20 years of exposure is reported to be as high as 20%.²⁶

The American Academy of Ophthalmology has long stated that retinopathy is a significant risk of hydroxychloroquine therapy and that patients taking hydroxychloroquine should therefore undergo routine retinal and visual field screening by an ophthalmologist.

Currently, initial screening followed by yearly screening beginning 5 years thereafter is recommended for patients at low risk of toxicity (Table 1).²⁷ Patients determined by an ophthalmologist to be at higher risk of retinopathy should be screened yearly. As identified by the American Academy of Ophthalmology, major risk factors for retinopathy include duration of use, concomitant tamoxifen exposure, significant renal disease, and preexisting retinal and macular disease.^26,28

Recommendations for hydroxychloroquine dosing and screening were recently revised, for 2 reasons. Initially, its manufacturers recommended that hydroxychloroquine dosage be no higher than 6.5 mg/kg of ideal body weight to prevent retinopathy.^1,29,30 However, it has recently been demonstrated that real body weight is a better predictor of risk of retinopathy than ideal body weight when dosing hydroxychloroquine, perhaps because of the increasing variance of real body weight in our patient population.²⁶

Further, an atypical pattern of retinopathy called pericentral retinopathy is more common in Asians. A study of about 200 patients with a history of hydroxychloroquine retinopathy, including 36 Asian patients, found that the pericentral pattern occurred in half the Asian patients but only 2% of the white patients.³¹ The mechanism for this finding is unclear, but because pericentral retinopathy spares the macula, it can be missed using standard screening methods. Therefore, the American Academy of Ophthalmology now recommends that the dose limit be reduced from 6.5 mg/kg of ideal body weight to no more than 5.0 mg/kg of real body weight (Table 2).²⁸

It is also recommended that screening methods such as automated visual fields and optical coherence tomography extend their fields beyond the macula in Asian patients to ensure that pericentral retinopathy is not missed.²⁸

Optical coherence tomography is a particularly useful tool in the ocular evaluation of patients taking hydroxychloroquine. It can detect subtle changes such as thinning of the foveal photoreceptor outer segment, thickening of the retinal pigment epithelium, and loss of the macular ganglion cell–inner plexiform layer before there are visible signs of retinopathy and before symptoms arise.³²

Currently, these guidelines are underutilized in clinical practice. Physician adherence to ophthalmologic guidelines is reported at about 50%.³³ This statistic is jarring, given the potential for permanent loss of vision in those with hydroxychloroquine-mediated retinopathy, and demonstrates the importance of reinforcing proper understanding of the use of hydroxychloroquine in clinical practice.

Cutaneous hyperpigmentation can occur with hydroxychloroquine use (Figure 1). The hyperpigmentation appears to be due to local bruising following deposition of iron in the soft tissue.

While the pigmentation may persist permanently and cause an undesirable cosmetic effect, it has not been associated with other adverse outcomes.

Myopathy is a rare adverse effect. In one case series, 3 of 214 patients treated with hydroxychloroquine developed hydroxychloroquine-induced myopathy.³⁵ Over the duration of their therapy, this was equivalent to an incidence of 1 case of myopathy in 100 patient-years of therapy. Myopathy improves with discontinuation of therapy, though it can persist for weeks, likely because of hydroxychloroquine’s prolonged elimination half-life.

Cardiomyopathy, specifically neurocardio­myopathy, is also an extremely rare adverse effect of hydroxychloroquine use. The mechanism is believed to be associated with the effect of hydroxychloroquine on lysosomal action, leading to an acquired lysosomal storage disorder with the typical cardiac hypertrophy and conduction abnormalities associated with this family of diseases.³⁶

Acute generalized exanthematous pustulosis is another rare complication of hydroxychloroquine therapy. The appearance of the reaction is similar to that of pustular psoriasis, with pustules overlying flaking and scaling skin. It usually resolves within 2 weeks after cessation of hydroxychloroquine therapy. In a select few cases, the reaction persists or waxes and wanes over a period of weeks to months, and longer durations of recovery are thought to be due to hydroxychloroquine’s long half-life, as in hydroxychloroquine-induced myopathy.³⁷

In view of this rare reaction, manufacturers of hydroxychloroquine recommend caution when using the drug in patients with psoriasis.¹

Hematologic abnormalities. In very rare cases, hydroxychloroquine is associated with hematologic abnormalities including agranulocytosis, anemia, aplastic anemia, leukopenia, and thrombocytopenia.¹

While no specific guidelines exist, caution is warranted when using hydroxychloroquine in patients with porphyria. Additionally, hydroxychloroquine and other antimalarials including primaquine have been associated with hemolysis in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. The risk of hemolysis is generally considered low except at high hydroxychloroquine doses in patients with severe G6PD deficiency.³⁸

For the above reasons, manufacturers recommended baseline and routine blood counts, and some providers screen patients for G6PD deficiency when prescribing hydroxychloroquine (Table 3).

PREGNANCY

Hydroxychloroquine is in pregnancy category C. Information is limited, and in view of the risks, the manufacturer says that it should be avoided in pregnancy.¹ Nevertheless, it is generally considered safe during pregnancy, and its benefits may make it acceptable to continue in a patient who becomes pregnant, in spite of the possible risks.

We favor continuing hydroxychloroquine. This drug has been associated with improved maternal and fetal outcomes in lupus patients. Its use during pregnancy has not been associated with congenital malformations. The adverse visual effects of long-term hydroxychloroquine use, namely retinopathy, have never been reported in children as a consequence of exposure in utero.

In addition, hydroxychloroquine is transmitted only in minute quantities in breast milk.³⁹ In pregnant women with systemic lupus erythematosus, hydroxychloroquine was associated with a lower risk of adverse outcomes, including preterm delivery and intrauterine growth restriction.⁴⁰ However, hydroxychloroquine is far more toxic when ingested directly by infants than in adults.¹

Maternal outcomes are also improved with the use of hydroxychloroquine. Stopping hydroxychloroquine during pregnancy in women with systemic lupus erythematosus is associated with significantly higher disease activity—fully twice as high as in those who continue hydroxychloroquine.⁴¹ These study results were corroborated in a small randomized trial in which pregnant women with lupus on placebo had significantly higher lupus disease activity scores than those pregnant women who were given hydroxychloroquine.⁴² The women taking hydroxychloroquine experienced no severe lupus flares for the duration of their pregnancies.

These findings suggest not only that hydroxychloroquine is safe in pregnancy, but also that it should be continued in lupus patients during pregnancy to prevent disease flares and adverse fetal outcomes.

Benefit in preclinical lupus?

Hydroxychloroquine has a consistently profound effect on outcomes in systemic lupus erythematosus. These findings, in addition to the more widespread use of antibody screening, have led to suggestions that hydroxychloroquine could be of benefit even before systemic lupus erythematosus is diagnosed.

A study in US military personnel found that patients taking hydroxychloroquine experienced a significantly longer lag time between first reported clinical symptoms of lupus and official diagnosis compared with  matched controls who also went on to develop the disease, averaging 1.08 vs 0.29 years to disease classification.⁴³ Those who used hydroxychloroquine also had lower rates of autoantibody accumulation. Therefore, hydroxychloroquine could be of benefit in carefully selected candidates at high risk of developing systemic lupus erythematosus.

The beneficial effects of hydroxychloroquine on patients with lupus and rheumatoid arthritis, in terms of primary measures of disease activity and secondary outcomes, were discovered fortuitously and were not the original intended targets of the drug. Because of its versatility, there are numerous other disease states in which hydroxychloroquine has shown a degree of benefit or has shown a potential for benefit.

Antiviral activity?

It has been suggested that antimalarial drugs could serve as adjunctive therapies against filoviruses such as Marburg and Ebola. There is a small body of in vitro and in vivo evidence that hydroxychloroquine could temper severe systemic inflammatory responses to filoviruses both through dysregulation of lysosomes and lysosomal pH (filoviruses have a pH-dependent mechanism of action) and through decreased production of tumor necrosis factor alpha and interferons. Heavy burdens of interferons and tumor necrosis factor alpha are associated with increased mortality rates in those infected with filoviruses.⁴⁴

Antineoplastic activity?

Hydroxychloroquine has undergone in vitro testing as an adjunct to cancer therapies. There are several mechanisms by which it is theorized that hydroxychloroquine could target malignant cells, including inhibition of multidrug resistance pumps or autophagy, improvement of chemotherapy cell penetration, potentiation of presentation of major histocompatibility complexes, or even intercalation directly into DNA.^45,46 However, it can also impair natural anticancer immunity and may allow cancer cells better nutrient supply through vascular effects.

In vitro studies have shown tumoricidal effects in lymphoma and melanoma, and inhibition of growth in lung, colon, breast, cervix, larynx, liver, and prostate cancers. In vivo studies have shown that hydroxychloroquine in high doses can prolong survival in glioblastoma.⁴⁵

Unfortunately, all of these theorized or observed effects are dose-dependent and likely require doses that exceed currently recommended maximums.

Negative chronotropic effect?

Hydroxychloroquine has been found to decrease the resting heart rate in a cumulative dose-dependent fashion.⁴⁷ Further, hydroxychloroquine has been known to increase digoxin levels, and the medications should not be used in combination.¹

Whether the decrease in resting heart rate is associated with harm or benefit and whether the effect is significant enough to be considered when implementing therapy remain unanswered and deserve further investigation, as does the primary use of hydroxychloroquine for beneficial lipid and glucose reduction in patients who are otherwise healthy.

CASE CONCLUSION

The patient described at the beginning of this article was provided with information on the risks and benefits of hydroxychloroquine for treatment of her arthritis and rash suggestive of mild systemic lupus, and she opted to begin therapy. Her baseline eye screening was within normal limits. Based on her weight of 62 kg, she was started on 300 mg of hydroxychloroquine daily.

She had no significant adverse effects from the medication and reported slow improvement in her rash and joint complaints over the next 2 months. She remained on hydroxychloroquine over the next year without adverse effects or new evidence of autoimmune disease.

A 29-year-old African American woman presents with a photosensitive malar rash, fatigue, morning stiffness, and swelling in her hands. She is found to have elevated anti­nuclear antibody at a titer of 1:320. A complete blood cell count demonstrates leukopenia and thrombocytopenia. Results of renal function testing and urinalysis are within normal limits. She has no other medical problems and no history of blood clots or pregnancy loss.

Her arthritis and rash suggest systemic lupus erythematosus. She is counseled to avoid sun exposure, and treatment with hydroxychloroquine is considered.

WHAT IS HYDROXYCHLOROQUINE?

Hydroxychloroquine was developed to treat malaria but was later found to have immunomodulatory properties. It is now approved by the US Food and Drug Administration for treatment of discoid lupus, systemic lupus ery­thematosus, and rheumatoid arthritis. It is also approved to treat malaria; however, of the several malarial parasites, only Plasmodium falciparum can still be cured by hydroxychloroquine, and growing resistance limits the geographic locations where this drug can be used effectively.^1,2

HISTORICAL BACKGROUND

Antimalarial drugs were discovered shortly before World War II. Their production was industrialized during the war because malaria was a leading cause of disease among soldiers, especially those deployed to the South Pacific.³

Atabrine (quinacrine), the first antimalarial widely used, had numerous side effects including yellowing of the skin. Aggressive research efforts to develop an alternative led to field testing of one of its derivative compounds, chloroquine, by the US Army in 1943. Continued chemical modification would create hydroxychloroquine, introduced in 1955.

A serendipitous consequence of the mass use of antimalarials during World War II was the discovery that they could be used to treat inflammatory arthritis and lupus. Eight years after the war ended, Shee⁴ reported that chloroquine had a beneficial effect on lupus and rheumatoid arthritis in US soldiers. Hydroxychloroquine is now the most commonly prescribed antimalarial for treatment of autoimmune disease.

HOW HYDROXYCHLOROQUINE WORKS

The primary mechanism by which hydroxychloroquine modulates systemic lupus erythematosus is by suppressing activation of Toll-like receptors, which exist on the surface of endosomes and play a significant role in the innate immune response and in autoimmune disease. Their activation is necessary for the expression of interferon-regulated genes and production of tumor necrosis factor alpha, which are key in the cell-mediated inflammatory response.

Antimalarial drugs such as hydroxychlor­oquine prevent Toll-like receptor activation by binding directly to nucleic acids in the activation pathway.⁵ In vitro studies show that blocking this pathway blunts the body’s primary cell-mediated inflammatory response; in vivo studies show that use of hydroxychloroquine is strongly correlated with a reduction in interferon alpha levels.⁶ The powerful effect of hydroxychloroquine on the cell-mediated pattern of inflammation found in lupus is consistent with this theory.

It was previously hypothesized that the immune-modulating effects of hydroxychloroquine were associated with a more general dysregulation of cellular lysosomes through inhibition of proteolysis or changes in cellular pH.⁷ This theory has since been displaced by the more specific and elegant mechanism described above.⁵

HOW WELL DOES IT WORK?

Benefit in systemic lupus erythematosus

Hydroxychloroquine has consistently demonstrated significant and multifaceted benefit in patients with systemic lupus erythematosus.

A systematic review of 95 articles⁸ concluded that this drug decreases lupus flares and decreases mortality rates in lupus patients by at least 50%, with a high level of evidence. Beneficial effects that had a moderate level of evidence were an increase in bone mineral density, fewer thrombotic events, and fewer cases of irreversible organ damage.

The preventive effect of hydroxychlor­oquine on thrombosis in lupus patients has been consistently demonstrated and is one of the key reasons the drug is considered a cornerstone of therapy in this disease.⁹ A nested case-control study of patients with lupus and thromboembolism demonstrated an odds ratio of 0.31 and relative risk reduction of 68% for those using antimalarials.¹⁰

Benefit in antiphospholipid antibody syndrome

Hydroxychloroquine prevents thrombosis in other diseases as well. For example, it has been shown to reduce the incidence of thrombotic events in patients with primary antiphospholipid syndrome.

In a retrospective cohort study in 114 patients with this disease, hydroxychloroquine significantly reduced the incidence of arterial thrombotic events over 10 years of follow-up (recurrence incidence 0 in those treated with hydroxychloroquine vs 1.14% in those not treated).¹¹ The study also tracked levels of antiphospholipid antibodies and reported that hydroxychloroquine significantly reduced the levels of antibodies to cardiolipin and beta-2 glycoprotein 1, both implicated in the pathology of thrombosis.¹¹

In vitro studies have also demonstrated that hydroxychloroquine can modulate a dysregulated inflammatory system to reduce thrombosis. For example, it has been shown that hydroxychloroquine can reverse platelet activation by antiphospholipid antibodies, prevent linking of antibody complexes to cell membranes, and promote proper membrane protein expression, thereby reducing the thrombotic qualities of antiphospholipid antibodies and even improving clearance times of antiphospholipid-related thrombi.¹²

Though there is less evidence, hydroxychloroquine has also shown benefit in rheumatoid arthritis, where it can be used by itself in mild disease or as part of combination therapy with active arthritis. Compared with biologic therapy in patients with early aggressive rheumatoid arthritis, triple therapy with methotrexate, sulfasalazine, and hydroxychloroquine was nearly as effective in terms of quality of life, and it cost only one-third as much, saving $20,000 per year of therapy per patient.¹³

Hydroxychloroquine has also been compared directly with chloroquine, its closest relation, in a large study incorporating patients with rheumatoid arthritis and patients with systemic lupus erythematosus. Patients using chloroquine experienced significantly more side effects, though it did prove marginally more effective.¹⁴

No benefit shown in Sjögren syndrome

Unfortunately, despite widespread use, hydroxychloroquine has not demonstrated positive clinical effects when used to treat primary Sjögren syndrome. Most notably, a 2014 randomized controlled trial of hydroxychloroquine vs placebo in 120 Sjögren patients found no significant improvement in primary symptoms of dryness, pain, or fatigue after 6 months of therapy.¹⁵

Metabolic benefits

Unexpectedly, hydroxychloroquine is associated with multiple metabolic benefits including improved lipid profiles and lower blood glucose levels. These findings, in addition to a reduced incidence of thrombosis, were initially reported in the Baltimore Lupus Cohort in 1996.¹⁶ Specifically, longitudinal evaluation of a cohort of lupus patients showed that hydroxychloroquine use was associated with a 7.6% reduction in total cholesterol and a 13.7% reduction in low-density lipoprotein cholesterol (LDL-C) over 3 months of therapy.¹⁷

Similar findings, including a reduction in LDL-C and an increase in high-density lipoprotein cholesterol, were strongly associated with the addition of hydroxychloroquine to methotrexate or to methotrexate and etanercept in a large cohort of rheumatoid arthritis patients followed over 2 years of therapy.¹⁸

In nondiabetic women with systemic lupus erythematosus or rheumatoid arthritis, average blood glucose was significantly lower in those taking hydroxychloroquine than in nonusers. The incidence of insulin resistance was also lower, but the difference was not statistically significant.¹⁹

Some have suggested that hydroxychloroquine may prevent diabetes mellitus. In a retrospective case series, compared with rheumatoid arthritis patients not taking the drug, patients treated with hydroxychloroquine for more than 4 years had a 25% lower risk of developing diabetes mellitus.²⁰

In view of these metabolic benefits, especially regarding lipid regulation, and the above described antithrombotic properties of hydroxychloroquine, some researchers have recently hypothesized that hydroxychloroquine may be of benefit in patients with coronary artery disease.²¹ They suggested that the inflammatory contribution to the mechanism of coronary artery disease could be lessened by hydroxychloroquine even in patients without lupus erythematosus or rheumatoid arthritis.

PHARMACOLOGIC PROPERTIES

Understanding the pharmacologic properties of hydroxychloroquine is key to using it appropriately in clinical practice.

The half-life of elimination of hydroxychloroquine is 40 to 50 days, with half of the drug excreted renally in a concentration-dependent fashion.^22,23 The drug reaches 95% of its steady-state concentration by about 6 months of therapy. Shorter durations of therapy do not provide adequate time for the drug to achieve steady-state concentration and may not allow patients and providers time to see its full clinical results. Therefore, its manufacturers recommend a 6-month trial of therapy to adequately determine if the drug improves symptoms.¹

The oral bioavailability of hydroxychloroquine is about 75%, but pharmacokinetics vary among individuals.^22,23 It has been suggested that this variability affects the efficacy of hydroxychloroquine. In a study of 300 patients with cutaneous lupus erythematosus, those whose treatment failed had significantly lower blood concentrations of hydroxychloroquine, while those who achieved complete remission had significantly higher concentrations.²⁴

Another study found that titrating doses to target therapeutic blood concentrations can reduce disease activity in cutaneous lupus erythematosus.²⁵ Measuring the blood concentration of hydroxychloroquine is not common in clinical practice but may have a role in select patients in whom initial therapy using a standard dosing regimen does not produce the desired results.

HOW SAFE IS HYDROXYCHLOROQUINE?

Hydroxychloroquine has numerous adverse effects, necessitating vigilance on the part of the prescriber. Most commonly reported are retinopathy, hyperpigmentation, myopathy, and skin reactions.¹

Retinopathy

Retinopathy’s irreversibility—the threat of permanent vision loss—and its substantial prevalence in patients with a large drug exposure history, have marked retinopathy as the most concerning potential toxicity. The risk of ocular toxicity increases with the cumulative hydroxychloroquine dose. The prevalence of retinopathy in those using the drug less than 10 years is less than 2%; in contrast, the prevalence in patients with more than 20 years of exposure is reported to be as high as 20%.²⁶

The American Academy of Ophthalmology has long stated that retinopathy is a significant risk of hydroxychloroquine therapy and that patients taking hydroxychloroquine should therefore undergo routine retinal and visual field screening by an ophthalmologist.

Currently, initial screening followed by yearly screening beginning 5 years thereafter is recommended for patients at low risk of toxicity (Table 1).²⁷ Patients determined by an ophthalmologist to be at higher risk of retinopathy should be screened yearly. As identified by the American Academy of Ophthalmology, major risk factors for retinopathy include duration of use, concomitant tamoxifen exposure, significant renal disease, and preexisting retinal and macular disease.^26,28

Recommendations for hydroxychloroquine dosing and screening were recently revised, for 2 reasons. Initially, its manufacturers recommended that hydroxychloroquine dosage be no higher than 6.5 mg/kg of ideal body weight to prevent retinopathy.^1,29,30 However, it has recently been demonstrated that real body weight is a better predictor of risk of retinopathy than ideal body weight when dosing hydroxychloroquine, perhaps because of the increasing variance of real body weight in our patient population.²⁶

Further, an atypical pattern of retinopathy called pericentral retinopathy is more common in Asians. A study of about 200 patients with a history of hydroxychloroquine retinopathy, including 36 Asian patients, found that the pericentral pattern occurred in half the Asian patients but only 2% of the white patients.³¹ The mechanism for this finding is unclear, but because pericentral retinopathy spares the macula, it can be missed using standard screening methods. Therefore, the American Academy of Ophthalmology now recommends that the dose limit be reduced from 6.5 mg/kg of ideal body weight to no more than 5.0 mg/kg of real body weight (Table 2).²⁸

It is also recommended that screening methods such as automated visual fields and optical coherence tomography extend their fields beyond the macula in Asian patients to ensure that pericentral retinopathy is not missed.²⁸

Optical coherence tomography is a particularly useful tool in the ocular evaluation of patients taking hydroxychloroquine. It can detect subtle changes such as thinning of the foveal photoreceptor outer segment, thickening of the retinal pigment epithelium, and loss of the macular ganglion cell–inner plexiform layer before there are visible signs of retinopathy and before symptoms arise.³²

Currently, these guidelines are underutilized in clinical practice. Physician adherence to ophthalmologic guidelines is reported at about 50%.³³ This statistic is jarring, given the potential for permanent loss of vision in those with hydroxychloroquine-mediated retinopathy, and demonstrates the importance of reinforcing proper understanding of the use of hydroxychloroquine in clinical practice.

Cutaneous hyperpigmentation can occur with hydroxychloroquine use (Figure 1). The hyperpigmentation appears to be due to local bruising following deposition of iron in the soft tissue.

While the pigmentation may persist permanently and cause an undesirable cosmetic effect, it has not been associated with other adverse outcomes.

Myopathy is a rare adverse effect. In one case series, 3 of 214 patients treated with hydroxychloroquine developed hydroxychloroquine-induced myopathy.³⁵ Over the duration of their therapy, this was equivalent to an incidence of 1 case of myopathy in 100 patient-years of therapy. Myopathy improves with discontinuation of therapy, though it can persist for weeks, likely because of hydroxychloroquine’s prolonged elimination half-life.

Cardiomyopathy, specifically neurocardio­myopathy, is also an extremely rare adverse effect of hydroxychloroquine use. The mechanism is believed to be associated with the effect of hydroxychloroquine on lysosomal action, leading to an acquired lysosomal storage disorder with the typical cardiac hypertrophy and conduction abnormalities associated with this family of diseases.³⁶

Acute generalized exanthematous pustulosis is another rare complication of hydroxychloroquine therapy. The appearance of the reaction is similar to that of pustular psoriasis, with pustules overlying flaking and scaling skin. It usually resolves within 2 weeks after cessation of hydroxychloroquine therapy. In a select few cases, the reaction persists or waxes and wanes over a period of weeks to months, and longer durations of recovery are thought to be due to hydroxychloroquine’s long half-life, as in hydroxychloroquine-induced myopathy.³⁷

In view of this rare reaction, manufacturers of hydroxychloroquine recommend caution when using the drug in patients with psoriasis.¹

Hematologic abnormalities. In very rare cases, hydroxychloroquine is associated with hematologic abnormalities including agranulocytosis, anemia, aplastic anemia, leukopenia, and thrombocytopenia.¹

While no specific guidelines exist, caution is warranted when using hydroxychloroquine in patients with porphyria. Additionally, hydroxychloroquine and other antimalarials including primaquine have been associated with hemolysis in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. The risk of hemolysis is generally considered low except at high hydroxychloroquine doses in patients with severe G6PD deficiency.³⁸

For the above reasons, manufacturers recommended baseline and routine blood counts, and some providers screen patients for G6PD deficiency when prescribing hydroxychloroquine (Table 3).

PREGNANCY

Hydroxychloroquine is in pregnancy category C. Information is limited, and in view of the risks, the manufacturer says that it should be avoided in pregnancy.¹ Nevertheless, it is generally considered safe during pregnancy, and its benefits may make it acceptable to continue in a patient who becomes pregnant, in spite of the possible risks.

We favor continuing hydroxychloroquine. This drug has been associated with improved maternal and fetal outcomes in lupus patients. Its use during pregnancy has not been associated with congenital malformations. The adverse visual effects of long-term hydroxychloroquine use, namely retinopathy, have never been reported in children as a consequence of exposure in utero.

In addition, hydroxychloroquine is transmitted only in minute quantities in breast milk.³⁹ In pregnant women with systemic lupus erythematosus, hydroxychloroquine was associated with a lower risk of adverse outcomes, including preterm delivery and intrauterine growth restriction.⁴⁰ However, hydroxychloroquine is far more toxic when ingested directly by infants than in adults.¹

Maternal outcomes are also improved with the use of hydroxychloroquine. Stopping hydroxychloroquine during pregnancy in women with systemic lupus erythematosus is associated with significantly higher disease activity—fully twice as high as in those who continue hydroxychloroquine.⁴¹ These study results were corroborated in a small randomized trial in which pregnant women with lupus on placebo had significantly higher lupus disease activity scores than those pregnant women who were given hydroxychloroquine.⁴² The women taking hydroxychloroquine experienced no severe lupus flares for the duration of their pregnancies.

These findings suggest not only that hydroxychloroquine is safe in pregnancy, but also that it should be continued in lupus patients during pregnancy to prevent disease flares and adverse fetal outcomes.

Benefit in preclinical lupus?

Hydroxychloroquine has a consistently profound effect on outcomes in systemic lupus erythematosus. These findings, in addition to the more widespread use of antibody screening, have led to suggestions that hydroxychloroquine could be of benefit even before systemic lupus erythematosus is diagnosed.

A study in US military personnel found that patients taking hydroxychloroquine experienced a significantly longer lag time between first reported clinical symptoms of lupus and official diagnosis compared with  matched controls who also went on to develop the disease, averaging 1.08 vs 0.29 years to disease classification.⁴³ Those who used hydroxychloroquine also had lower rates of autoantibody accumulation. Therefore, hydroxychloroquine could be of benefit in carefully selected candidates at high risk of developing systemic lupus erythematosus.

The beneficial effects of hydroxychloroquine on patients with lupus and rheumatoid arthritis, in terms of primary measures of disease activity and secondary outcomes, were discovered fortuitously and were not the original intended targets of the drug. Because of its versatility, there are numerous other disease states in which hydroxychloroquine has shown a degree of benefit or has shown a potential for benefit.

Antiviral activity?

It has been suggested that antimalarial drugs could serve as adjunctive therapies against filoviruses such as Marburg and Ebola. There is a small body of in vitro and in vivo evidence that hydroxychloroquine could temper severe systemic inflammatory responses to filoviruses both through dysregulation of lysosomes and lysosomal pH (filoviruses have a pH-dependent mechanism of action) and through decreased production of tumor necrosis factor alpha and interferons. Heavy burdens of interferons and tumor necrosis factor alpha are associated with increased mortality rates in those infected with filoviruses.⁴⁴

Antineoplastic activity?

Hydroxychloroquine has undergone in vitro testing as an adjunct to cancer therapies. There are several mechanisms by which it is theorized that hydroxychloroquine could target malignant cells, including inhibition of multidrug resistance pumps or autophagy, improvement of chemotherapy cell penetration, potentiation of presentation of major histocompatibility complexes, or even intercalation directly into DNA.^45,46 However, it can also impair natural anticancer immunity and may allow cancer cells better nutrient supply through vascular effects.

In vitro studies have shown tumoricidal effects in lymphoma and melanoma, and inhibition of growth in lung, colon, breast, cervix, larynx, liver, and prostate cancers. In vivo studies have shown that hydroxychloroquine in high doses can prolong survival in glioblastoma.⁴⁵

Unfortunately, all of these theorized or observed effects are dose-dependent and likely require doses that exceed currently recommended maximums.

Negative chronotropic effect?

Hydroxychloroquine has been found to decrease the resting heart rate in a cumulative dose-dependent fashion.⁴⁷ Further, hydroxychloroquine has been known to increase digoxin levels, and the medications should not be used in combination.¹

Whether the decrease in resting heart rate is associated with harm or benefit and whether the effect is significant enough to be considered when implementing therapy remain unanswered and deserve further investigation, as does the primary use of hydroxychloroquine for beneficial lipid and glucose reduction in patients who are otherwise healthy.

CASE CONCLUSION

The patient described at the beginning of this article was provided with information on the risks and benefits of hydroxychloroquine for treatment of her arthritis and rash suggestive of mild systemic lupus, and she opted to begin therapy. Her baseline eye screening was within normal limits. Based on her weight of 62 kg, she was started on 300 mg of hydroxychloroquine daily.

She had no significant adverse effects from the medication and reported slow improvement in her rash and joint complaints over the next 2 months. She remained on hydroxychloroquine over the next year without adverse effects or new evidence of autoimmune disease.

A 29-year-old African American woman presents with a photosensitive malar rash, fatigue, morning stiffness, and swelling in her hands. She is found to have elevated anti­nuclear antibody at a titer of 1:320. A complete blood cell count demonstrates leukopenia and thrombocytopenia. Results of renal function testing and urinalysis are within normal limits. She has no other medical problems and no history of blood clots or pregnancy loss.

Her arthritis and rash suggest systemic lupus erythematosus. She is counseled to avoid sun exposure, and treatment with hydroxychloroquine is considered.

WHAT IS HYDROXYCHLOROQUINE?

Hydroxychloroquine was developed to treat malaria but was later found to have immunomodulatory properties. It is now approved by the US Food and Drug Administration for treatment of discoid lupus, systemic lupus ery­thematosus, and rheumatoid arthritis. It is also approved to treat malaria; however, of the several malarial parasites, only Plasmodium falciparum can still be cured by hydroxychloroquine, and growing resistance limits the geographic locations where this drug can be used effectively.^1,2

HISTORICAL BACKGROUND

Antimalarial drugs were discovered shortly before World War II. Their production was industrialized during the war because malaria was a leading cause of disease among soldiers, especially those deployed to the South Pacific.³

Atabrine (quinacrine), the first antimalarial widely used, had numerous side effects including yellowing of the skin. Aggressive research efforts to develop an alternative led to field testing of one of its derivative compounds, chloroquine, by the US Army in 1943. Continued chemical modification would create hydroxychloroquine, introduced in 1955.

A serendipitous consequence of the mass use of antimalarials during World War II was the discovery that they could be used to treat inflammatory arthritis and lupus. Eight years after the war ended, Shee⁴ reported that chloroquine had a beneficial effect on lupus and rheumatoid arthritis in US soldiers. Hydroxychloroquine is now the most commonly prescribed antimalarial for treatment of autoimmune disease.

HOW HYDROXYCHLOROQUINE WORKS

The primary mechanism by which hydroxychloroquine modulates systemic lupus erythematosus is by suppressing activation of Toll-like receptors, which exist on the surface of endosomes and play a significant role in the innate immune response and in autoimmune disease. Their activation is necessary for the expression of interferon-regulated genes and production of tumor necrosis factor alpha, which are key in the cell-mediated inflammatory response.

Antimalarial drugs such as hydroxychlor­oquine prevent Toll-like receptor activation by binding directly to nucleic acids in the activation pathway.⁵ In vitro studies show that blocking this pathway blunts the body’s primary cell-mediated inflammatory response; in vivo studies show that use of hydroxychloroquine is strongly correlated with a reduction in interferon alpha levels.⁶ The powerful effect of hydroxychloroquine on the cell-mediated pattern of inflammation found in lupus is consistent with this theory.

It was previously hypothesized that the immune-modulating effects of hydroxychloroquine were associated with a more general dysregulation of cellular lysosomes through inhibition of proteolysis or changes in cellular pH.⁷ This theory has since been displaced by the more specific and elegant mechanism described above.⁵

HOW WELL DOES IT WORK?

Benefit in systemic lupus erythematosus

Hydroxychloroquine has consistently demonstrated significant and multifaceted benefit in patients with systemic lupus erythematosus.

A systematic review of 95 articles⁸ concluded that this drug decreases lupus flares and decreases mortality rates in lupus patients by at least 50%, with a high level of evidence. Beneficial effects that had a moderate level of evidence were an increase in bone mineral density, fewer thrombotic events, and fewer cases of irreversible organ damage.

The preventive effect of hydroxychlor­oquine on thrombosis in lupus patients has been consistently demonstrated and is one of the key reasons the drug is considered a cornerstone of therapy in this disease.⁹ A nested case-control study of patients with lupus and thromboembolism demonstrated an odds ratio of 0.31 and relative risk reduction of 68% for those using antimalarials.¹⁰

Benefit in antiphospholipid antibody syndrome

Hydroxychloroquine prevents thrombosis in other diseases as well. For example, it has been shown to reduce the incidence of thrombotic events in patients with primary antiphospholipid syndrome.

In a retrospective cohort study in 114 patients with this disease, hydroxychloroquine significantly reduced the incidence of arterial thrombotic events over 10 years of follow-up (recurrence incidence 0 in those treated with hydroxychloroquine vs 1.14% in those not treated).¹¹ The study also tracked levels of antiphospholipid antibodies and reported that hydroxychloroquine significantly reduced the levels of antibodies to cardiolipin and beta-2 glycoprotein 1, both implicated in the pathology of thrombosis.¹¹

In vitro studies have also demonstrated that hydroxychloroquine can modulate a dysregulated inflammatory system to reduce thrombosis. For example, it has been shown that hydroxychloroquine can reverse platelet activation by antiphospholipid antibodies, prevent linking of antibody complexes to cell membranes, and promote proper membrane protein expression, thereby reducing the thrombotic qualities of antiphospholipid antibodies and even improving clearance times of antiphospholipid-related thrombi.¹²

Though there is less evidence, hydroxychloroquine has also shown benefit in rheumatoid arthritis, where it can be used by itself in mild disease or as part of combination therapy with active arthritis. Compared with biologic therapy in patients with early aggressive rheumatoid arthritis, triple therapy with methotrexate, sulfasalazine, and hydroxychloroquine was nearly as effective in terms of quality of life, and it cost only one-third as much, saving $20,000 per year of therapy per patient.¹³

Hydroxychloroquine has also been compared directly with chloroquine, its closest relation, in a large study incorporating patients with rheumatoid arthritis and patients with systemic lupus erythematosus. Patients using chloroquine experienced significantly more side effects, though it did prove marginally more effective.¹⁴

No benefit shown in Sjögren syndrome

Unfortunately, despite widespread use, hydroxychloroquine has not demonstrated positive clinical effects when used to treat primary Sjögren syndrome. Most notably, a 2014 randomized controlled trial of hydroxychloroquine vs placebo in 120 Sjögren patients found no significant improvement in primary symptoms of dryness, pain, or fatigue after 6 months of therapy.¹⁵

Metabolic benefits

Unexpectedly, hydroxychloroquine is associated with multiple metabolic benefits including improved lipid profiles and lower blood glucose levels. These findings, in addition to a reduced incidence of thrombosis, were initially reported in the Baltimore Lupus Cohort in 1996.¹⁶ Specifically, longitudinal evaluation of a cohort of lupus patients showed that hydroxychloroquine use was associated with a 7.6% reduction in total cholesterol and a 13.7% reduction in low-density lipoprotein cholesterol (LDL-C) over 3 months of therapy.¹⁷

Similar findings, including a reduction in LDL-C and an increase in high-density lipoprotein cholesterol, were strongly associated with the addition of hydroxychloroquine to methotrexate or to methotrexate and etanercept in a large cohort of rheumatoid arthritis patients followed over 2 years of therapy.¹⁸

In nondiabetic women with systemic lupus erythematosus or rheumatoid arthritis, average blood glucose was significantly lower in those taking hydroxychloroquine than in nonusers. The incidence of insulin resistance was also lower, but the difference was not statistically significant.¹⁹

Some have suggested that hydroxychloroquine may prevent diabetes mellitus. In a retrospective case series, compared with rheumatoid arthritis patients not taking the drug, patients treated with hydroxychloroquine for more than 4 years had a 25% lower risk of developing diabetes mellitus.²⁰

In view of these metabolic benefits, especially regarding lipid regulation, and the above described antithrombotic properties of hydroxychloroquine, some researchers have recently hypothesized that hydroxychloroquine may be of benefit in patients with coronary artery disease.²¹ They suggested that the inflammatory contribution to the mechanism of coronary artery disease could be lessened by hydroxychloroquine even in patients without lupus erythematosus or rheumatoid arthritis.

PHARMACOLOGIC PROPERTIES

Understanding the pharmacologic properties of hydroxychloroquine is key to using it appropriately in clinical practice.

The half-life of elimination of hydroxychloroquine is 40 to 50 days, with half of the drug excreted renally in a concentration-dependent fashion.^22,23 The drug reaches 95% of its steady-state concentration by about 6 months of therapy. Shorter durations of therapy do not provide adequate time for the drug to achieve steady-state concentration and may not allow patients and providers time to see its full clinical results. Therefore, its manufacturers recommend a 6-month trial of therapy to adequately determine if the drug improves symptoms.¹

The oral bioavailability of hydroxychloroquine is about 75%, but pharmacokinetics vary among individuals.^22,23 It has been suggested that this variability affects the efficacy of hydroxychloroquine. In a study of 300 patients with cutaneous lupus erythematosus, those whose treatment failed had significantly lower blood concentrations of hydroxychloroquine, while those who achieved complete remission had significantly higher concentrations.²⁴

Another study found that titrating doses to target therapeutic blood concentrations can reduce disease activity in cutaneous lupus erythematosus.²⁵ Measuring the blood concentration of hydroxychloroquine is not common in clinical practice but may have a role in select patients in whom initial therapy using a standard dosing regimen does not produce the desired results.

HOW SAFE IS HYDROXYCHLOROQUINE?

Hydroxychloroquine has numerous adverse effects, necessitating vigilance on the part of the prescriber. Most commonly reported are retinopathy, hyperpigmentation, myopathy, and skin reactions.¹

Retinopathy

Retinopathy’s irreversibility—the threat of permanent vision loss—and its substantial prevalence in patients with a large drug exposure history, have marked retinopathy as the most concerning potential toxicity. The risk of ocular toxicity increases with the cumulative hydroxychloroquine dose. The prevalence of retinopathy in those using the drug less than 10 years is less than 2%; in contrast, the prevalence in patients with more than 20 years of exposure is reported to be as high as 20%.²⁶

The American Academy of Ophthalmology has long stated that retinopathy is a significant risk of hydroxychloroquine therapy and that patients taking hydroxychloroquine should therefore undergo routine retinal and visual field screening by an ophthalmologist.

Currently, initial screening followed by yearly screening beginning 5 years thereafter is recommended for patients at low risk of toxicity (Table 1).²⁷ Patients determined by an ophthalmologist to be at higher risk of retinopathy should be screened yearly. As identified by the American Academy of Ophthalmology, major risk factors for retinopathy include duration of use, concomitant tamoxifen exposure, significant renal disease, and preexisting retinal and macular disease.^26,28

Recommendations for hydroxychloroquine dosing and screening were recently revised, for 2 reasons. Initially, its manufacturers recommended that hydroxychloroquine dosage be no higher than 6.5 mg/kg of ideal body weight to prevent retinopathy.^1,29,30 However, it has recently been demonstrated that real body weight is a better predictor of risk of retinopathy than ideal body weight when dosing hydroxychloroquine, perhaps because of the increasing variance of real body weight in our patient population.²⁶

Further, an atypical pattern of retinopathy called pericentral retinopathy is more common in Asians. A study of about 200 patients with a history of hydroxychloroquine retinopathy, including 36 Asian patients, found that the pericentral pattern occurred in half the Asian patients but only 2% of the white patients.³¹ The mechanism for this finding is unclear, but because pericentral retinopathy spares the macula, it can be missed using standard screening methods. Therefore, the American Academy of Ophthalmology now recommends that the dose limit be reduced from 6.5 mg/kg of ideal body weight to no more than 5.0 mg/kg of real body weight (Table 2).²⁸

It is also recommended that screening methods such as automated visual fields and optical coherence tomography extend their fields beyond the macula in Asian patients to ensure that pericentral retinopathy is not missed.²⁸

Optical coherence tomography is a particularly useful tool in the ocular evaluation of patients taking hydroxychloroquine. It can detect subtle changes such as thinning of the foveal photoreceptor outer segment, thickening of the retinal pigment epithelium, and loss of the macular ganglion cell–inner plexiform layer before there are visible signs of retinopathy and before symptoms arise.³²

Currently, these guidelines are underutilized in clinical practice. Physician adherence to ophthalmologic guidelines is reported at about 50%.³³ This statistic is jarring, given the potential for permanent loss of vision in those with hydroxychloroquine-mediated retinopathy, and demonstrates the importance of reinforcing proper understanding of the use of hydroxychloroquine in clinical practice.

Cutaneous hyperpigmentation can occur with hydroxychloroquine use (Figure 1). The hyperpigmentation appears to be due to local bruising following deposition of iron in the soft tissue.

While the pigmentation may persist permanently and cause an undesirable cosmetic effect, it has not been associated with other adverse outcomes.

Myopathy is a rare adverse effect. In one case series, 3 of 214 patients treated with hydroxychloroquine developed hydroxychloroquine-induced myopathy.³⁵ Over the duration of their therapy, this was equivalent to an incidence of 1 case of myopathy in 100 patient-years of therapy. Myopathy improves with discontinuation of therapy, though it can persist for weeks, likely because of hydroxychloroquine’s prolonged elimination half-life.

Cardiomyopathy, specifically neurocardio­myopathy, is also an extremely rare adverse effect of hydroxychloroquine use. The mechanism is believed to be associated with the effect of hydroxychloroquine on lysosomal action, leading to an acquired lysosomal storage disorder with the typical cardiac hypertrophy and conduction abnormalities associated with this family of diseases.³⁶

Acute generalized exanthematous pustulosis is another rare complication of hydroxychloroquine therapy. The appearance of the reaction is similar to that of pustular psoriasis, with pustules overlying flaking and scaling skin. It usually resolves within 2 weeks after cessation of hydroxychloroquine therapy. In a select few cases, the reaction persists or waxes and wanes over a period of weeks to months, and longer durations of recovery are thought to be due to hydroxychloroquine’s long half-life, as in hydroxychloroquine-induced myopathy.³⁷

In view of this rare reaction, manufacturers of hydroxychloroquine recommend caution when using the drug in patients with psoriasis.¹

Hematologic abnormalities. In very rare cases, hydroxychloroquine is associated with hematologic abnormalities including agranulocytosis, anemia, aplastic anemia, leukopenia, and thrombocytopenia.¹

While no specific guidelines exist, caution is warranted when using hydroxychloroquine in patients with porphyria. Additionally, hydroxychloroquine and other antimalarials including primaquine have been associated with hemolysis in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. The risk of hemolysis is generally considered low except at high hydroxychloroquine doses in patients with severe G6PD deficiency.³⁸

For the above reasons, manufacturers recommended baseline and routine blood counts, and some providers screen patients for G6PD deficiency when prescribing hydroxychloroquine (Table 3).

PREGNANCY

Hydroxychloroquine is in pregnancy category C. Information is limited, and in view of the risks, the manufacturer says that it should be avoided in pregnancy.¹ Nevertheless, it is generally considered safe during pregnancy, and its benefits may make it acceptable to continue in a patient who becomes pregnant, in spite of the possible risks.

We favor continuing hydroxychloroquine. This drug has been associated with improved maternal and fetal outcomes in lupus patients. Its use during pregnancy has not been associated with congenital malformations. The adverse visual effects of long-term hydroxychloroquine use, namely retinopathy, have never been reported in children as a consequence of exposure in utero.

In addition, hydroxychloroquine is transmitted only in minute quantities in breast milk.³⁹ In pregnant women with systemic lupus erythematosus, hydroxychloroquine was associated with a lower risk of adverse outcomes, including preterm delivery and intrauterine growth restriction.⁴⁰ However, hydroxychloroquine is far more toxic when ingested directly by infants than in adults.¹

Maternal outcomes are also improved with the use of hydroxychloroquine. Stopping hydroxychloroquine during pregnancy in women with systemic lupus erythematosus is associated with significantly higher disease activity—fully twice as high as in those who continue hydroxychloroquine.⁴¹ These study results were corroborated in a small randomized trial in which pregnant women with lupus on placebo had significantly higher lupus disease activity scores than those pregnant women who were given hydroxychloroquine.⁴² The women taking hydroxychloroquine experienced no severe lupus flares for the duration of their pregnancies.

These findings suggest not only that hydroxychloroquine is safe in pregnancy, but also that it should be continued in lupus patients during pregnancy to prevent disease flares and adverse fetal outcomes.

Benefit in preclinical lupus?

Hydroxychloroquine has a consistently profound effect on outcomes in systemic lupus erythematosus. These findings, in addition to the more widespread use of antibody screening, have led to suggestions that hydroxychloroquine could be of benefit even before systemic lupus erythematosus is diagnosed.

A study in US military personnel found that patients taking hydroxychloroquine experienced a significantly longer lag time between first reported clinical symptoms of lupus and official diagnosis compared with  matched controls who also went on to develop the disease, averaging 1.08 vs 0.29 years to disease classification.⁴³ Those who used hydroxychloroquine also had lower rates of autoantibody accumulation. Therefore, hydroxychloroquine could be of benefit in carefully selected candidates at high risk of developing systemic lupus erythematosus.

The beneficial effects of hydroxychloroquine on patients with lupus and rheumatoid arthritis, in terms of primary measures of disease activity and secondary outcomes, were discovered fortuitously and were not the original intended targets of the drug. Because of its versatility, there are numerous other disease states in which hydroxychloroquine has shown a degree of benefit or has shown a potential for benefit.

Antiviral activity?

It has been suggested that antimalarial drugs could serve as adjunctive therapies against filoviruses such as Marburg and Ebola. There is a small body of in vitro and in vivo evidence that hydroxychloroquine could temper severe systemic inflammatory responses to filoviruses both through dysregulation of lysosomes and lysosomal pH (filoviruses have a pH-dependent mechanism of action) and through decreased production of tumor necrosis factor alpha and interferons. Heavy burdens of interferons and tumor necrosis factor alpha are associated with increased mortality rates in those infected with filoviruses.⁴⁴

Antineoplastic activity?

Hydroxychloroquine has undergone in vitro testing as an adjunct to cancer therapies. There are several mechanisms by which it is theorized that hydroxychloroquine could target malignant cells, including inhibition of multidrug resistance pumps or autophagy, improvement of chemotherapy cell penetration, potentiation of presentation of major histocompatibility complexes, or even intercalation directly into DNA.^45,46 However, it can also impair natural anticancer immunity and may allow cancer cells better nutrient supply through vascular effects.

In vitro studies have shown tumoricidal effects in lymphoma and melanoma, and inhibition of growth in lung, colon, breast, cervix, larynx, liver, and prostate cancers. In vivo studies have shown that hydroxychloroquine in high doses can prolong survival in glioblastoma.⁴⁵

Unfortunately, all of these theorized or observed effects are dose-dependent and likely require doses that exceed currently recommended maximums.

Negative chronotropic effect?

Hydroxychloroquine has been found to decrease the resting heart rate in a cumulative dose-dependent fashion.⁴⁷ Further, hydroxychloroquine has been known to increase digoxin levels, and the medications should not be used in combination.¹

Whether the decrease in resting heart rate is associated with harm or benefit and whether the effect is significant enough to be considered when implementing therapy remain unanswered and deserve further investigation, as does the primary use of hydroxychloroquine for beneficial lipid and glucose reduction in patients who are otherwise healthy.

CASE CONCLUSION

The patient described at the beginning of this article was provided with information on the risks and benefits of hydroxychloroquine for treatment of her arthritis and rash suggestive of mild systemic lupus, and she opted to begin therapy. Her baseline eye screening was within normal limits. Based on her weight of 62 kg, she was started on 300 mg of hydroxychloroquine daily.

She had no significant adverse effects from the medication and reported slow improvement in her rash and joint complaints over the next 2 months. She remained on hydroxychloroquine over the next year without adverse effects or new evidence of autoimmune disease.

Pharmacologic treatment options for many substance use disorders (SUDs) are limited. This is especially true for cocaine use disorder and cannabis use disorder, for which there are no FDA-approved medications. FDA-approved medications for other SUDs often take the form of replacement or agonist therapies (eg, nicotine replacement therapy) that substitute the effects of the substance to aid in cessation. Other pharmacotherapies treat symptoms of withdrawal, reduce craving, or provide aversive counter-conditioning if the patient consumes the substance while on the medication (eg, disulfiram).

The over-the-counter (OTC) antioxidant N-acetylcysteine (NAC) may be a potential treatment for SUDs. Although NAC is not approved by the FDA for treating SUDs, its proposed mechanism of action differs from that of current FDA-approved medications for SUDs. NAC’s potential for broad applicability, favorable adverse-effect profile, accessibility, and low cost make it an intriguing option for patients with multiple comorbidities, and potentially for individuals with polysubstance use. This article reviews the current evidence supporting NAC for treating SUDs, to provide insight about which patients may benefit from NAC and under which circumstances they are most likely to benefit.

NAC may correct glutamate dysregulation

Approximately 85% of individuals with an SUD do not seek treatment for it, and those who do are older, have a longer history of use, have more severe dependence, and have sought treatment numerous times before.¹ By the time most people seek treatment, years of chronic substance use have likely led to significant brain-related adaptations. Individuals with SUDs often indicate that their substance use began as a pleasurable activity—the effects of the drug were enjoyable and they were motivated to use it again. With repeated substance use, they may begin to develop a stronger urge to use the drug, driven not necessarily by a desire for pleasure, but by compulsion.²

Numerous neural adaptations underlie the transition from “liking” a substance to engaging in the compulsive use that is characteristic of an SUD.² For example, repeated use of an addictive substance may result in excess glutamate in the nucleus accumbens,^3,4 an area of the brain that plays a critical role in motivation and learning. As a result, it has been proposed that pharmacotherapies that help correct glutamate dysregulation may be effective in promoting abstinence or preventing relapse to a substance.^5,6

NAC may reverse the neural dysfunction seen in SUDs. As an OTC antioxidant that impacts glutamatergic functioning in the brain, NAC has long been used to treat acetaminophen overdose; however, in recent years, researchers have begun to tap its potential for treating substance use and psychiatric disorders. NAC is thought to upregulate the glutamate transporter (GLT-1) that removes excess glutamate from the nucleus accumbens.⁶ Several published reviews provide more in-depth information about the neurobiology of NAC.^6-10

The adverse-effect profile of NAC is relatively benign. Nausea, vomiting, diarrhea, and sleepiness are relatively infrequent and mild.^11,12 The bioavailability of NAC is about 4% to 9%, with an approximate half-life of 6.25 hours when orally administered.¹³ Because NAC is classified as an OTC supplement, the potency and preparation may vary by supplier. To maximize consistency, NAC should be obtained from a supplier that meets United States Pharmacopeia (USP) standards.

NAC for SUDs: Emerging evidence

Several recent reviews have described the efficacy of NAC for SUDs and other psychiatric disorders. Here we summarize the current research examining the efficacy of NAC for stimulant (ie, cocaine and methamphetamine), cannabis, tobacco, and alcohol use disorders.

Continue to: Stimulant use disorders

Stimulant use disorders. The United Nations Office for Drugs and Crime estimates that worldwide, more than 18 million people use cocaine and more than 35 million use amphetamines.¹⁴ There are currently no FDA-approved treatments for stimulant use disorders, and clinicians treating patients with cocaine or amphetamine dependence often are at a loss for how best to promote abstinence. Recent studies suggest that NAC may decrease drug-seeking behavior and cravings in adults who seek treatment. The results of studies examining NAC for treating cocaine use and methamphetamine use are summarized in Table 1^15-17 and Table 2,^18,19 respectively.

Cocaine cessation and relapse prevention. Several small pilot projects^15,16 found that compared with placebo, various doses of NAC reduced craving (as measured with a visual analog scale). However, in a double-blind, placebo-controlled study, NAC did not decrease cravings or use after 8 weeks of treatment in individuals with cocaine use disorder who were still using cocaine (ie, they had not yet become abstinent). Interestingly, those who were abstinent when treatment began reported lower craving and remained abstinent longer if they received NAC (vs placebo), which suggests that NAC may be useful for preventing relapse.¹⁷

Methamphetamine cessation and relapse prevention. One study (N = 32) that evaluated the use of NAC, 1,200 mg/d for 4 weeks, vs placebo found reduced cravings among methamphetamine users who were seeking treatment.¹⁸ In contrast, a study of 31 methamphetamine users who were not seeking treatment evaluated the use of NAC, 2,400 mg/d, plus naltrexone, 200 mg/d, vs placebo for 8 weeks.¹⁹ It found no significant differences in craving or use patterns. Further research is needed to optimize the use of NAC for stimulant use disorders, and to better understand the role that abstinence plays.

Appropriate populations. The most support for use of NAC has been as an anti-relapse agent in treatment-seeking adults.

Continue to: Safety and dosing

Safety and dosing. Suggested dosages for the treatment of cocaine use disorder range from 1,200 to 3,600 mg/d (typically 600 to 1,800 mg twice daily, due to NAC’s short half-life), with higher retention rates noted in individuals who received 2,400 mg/d and 3,600 mg/d.¹⁶

Clinical implications. NAC is thought to act as an anti-relapse agent, rather than an agent that can help someone who is actively using stimulants to stop. Consequently, NAC will likely be most helpful for patients who are motivated to quit and are abstinent when they start taking NAC; however, this hypothesis needs further testing.

Cannabis use disorder

There are no FDA-approved treatments for cannabis use disorder. Individuals who use marijuana or other forms of cannabis may be less likely to report negative consequences or seek treatment compared with those who use other substances. Approximately 9% of individuals who use marijuana develop cannabis use disorder²⁰; those who begin using marijuana earlier in adolescence are at increased risk.²¹ Commonly reported reasons for wanting to stop using marijuana include being concerned about health consequences, regaining or demonstrating self-control, saving money, avoiding legal consequences, obtaining or keeping employment, and reducing interpersonal conflict.^22,23 Table 3^24-27 summarizes initial evidence that suggests NAC may be particularly useful in reducing marijuana use among adolescents (age 15 to 21).^24,25

Cessation. An open-label, pilot clinical trial found significant reductions in self-reported marijuana use and craving—but not in biomarkers of use—among 24 adolescents after 4 weeks of NAC, 1,200 mg twice daily.²⁴ In an 8-week, double-blind, randomized controlled trial of 116 adolescents, NAC, 1,200 mg twice daily, plus contingency management doubled the odds of abstinence, but had no effect on self-reported craving or use.^25,26 In a sample of 302 adults, a 12-week trial of NAC, 1,200 mg twice daily, plus contingency management was no more effective than contingency management alone in promoting abstinence.²⁷

Continue to: Appropriate populations

Appropriate populations. Evidence is stronger for use of NAC among adolescents (age 15 to 21) than for individuals older than age 21.^25,27 Further research is needed to explore potential reasons for age-specific effects.

Safety and dosing. A safe and potentially efficacious dosage for the treatment of cannabis use disorder is 2,400 mg/d (1,200 mg twice daily).^24,25,27

Clinical implications. Combined with contingency management, NAC might be efficacious for adolescents with cannabis use disorder, with treatment gains evident by the fourth week of treatment.^24,25 To date, no clinical trials have examined the efficacy of NAC for treating cannabis use disorder without adjunctive contingency management, and research is needed to isolate the clinical effect of NAC among adolescents.

Tobacco use disorder

Cigarette smoking remains a leading cause of preventable death in the United States,²⁸ and nearly 70% of people who start using tobacco become dependent.²⁰ Existing FDA-approved treatments include nicotine replacement products, varenicline, and bupropion. Even though efficacious treatments exist, successful and sustained quit attempts are infrequent.²⁹ NAC may exert a complementary effect to existing tobacco cessation interventions, such as varenicline.³⁰ While these medications promote abstinence, NAC may be particularly beneficial in preventing relapse after abstinence has been achieved (Table 4^30-36).

Continue to: Cessation and relapse prevention

Cessation and relapse prevention. Several pilot studies found that adult smokers who received NAC (alone or in combination with another treatment) had lower carbon monoxide levels,^31,32 smoked fewer cigarettes,^32,33 and had fewer self-reported symptoms of nicotine dependence³⁴ and/or less craving for cigarettes.³¹ However, one study of 33 smokers did not find a reduction in craving or carbon monoxide for NAC compared with placebo.³³ Another pilot study of 22 young adult smokers found that those who received NAC rated their first cigarette after treatment (smoked in the laboratory) as less rewarding, relative to smokers who received a placebo.³⁵

Secondary analyses of adults with bipolar disorder³⁶ and adolescents with cannabis use disorder³⁷ found no decreases in tobacco use among those who received NAC compared with placebo. However, the studies in these analyses did not specifically recruit tobacco users, and participants who were tobacco users were not necessarily interested in quitting. This may partially explain discrepant findings.

Appropriate populations. NAC has been studied mostly in adult cigarette smokers.

Safety and dosing. Suggested dosages for treating tobacco use disorder range from 1,200 to 3,600 mg/d (600 to 1,800 mg twice daily).

Continue to: Clinical implications

Clinical implications. Data on NAC’s efficacy for tobacco use disorder come from small, pilot trials. Although initial evidence is promising, it is premature to suggest NAC for smoking cessation until a fully powered, randomized clinical trial provides evidence of efficacy.

Alcohol use disorder

Alcohol use disorders are widely prevalent; 13.9% of U.S. adults met criteria in the past year, and 29.1% of U.S. adults meet criteria in their lifetime.³⁸ Alcohol use disorders can result in significant negative consequences, including relationship problems, violent behavior, medical problems, and death. Existing FDA-approved medications for alcohol use disorder include naltrexone, acamprosate, and disulfiram.

Due to the severe potential health consequences of alcohol, NAC has been examined as a possible aid in preventing relapse. However, most studies have been conducted using animals. Three studies have examined alcohol use in humans (Table 5^36,39,40). One was a pilot study,³⁹ and the other 2 were secondary data analyses.^36,40 None of them specifically focused on alcohol use disorders. A pilot study of 35 veterans with co-occurring posttraumautic stress disorder (PTSD) and SUDs (82% of whom had an alcohol use disorder) found that compared with placebo, NAC significantly decreased PTSD symptoms, craving, and depression.³⁹ In a study of 75 adults with bipolar disorder, secondary alcohol use was not significantly reduced.³⁶ However, one study suggested that NAC may decrease adolescent alcohol and marijuana co-use.⁴⁰ Future work is needed to examine the potential clinical utility of NAC in individuals with alcohol use disorders.

Findings from animal studies indicate that NAC may:

• reduce alcohol-seeking⁴¹
• reduce withdrawal symptoms⁴²
• reduce the teratogenic effects of alcohol⁴³
• prevent alcohol toxicity⁴⁴
• reduce health-related consequences of alcohol (eg, myocardial oxidative stress⁴⁵ and alcohol-related steatohepatitis⁴⁶).

Continue to: Appropriate populations

Appropriate populations. Pilot studies have suggested that appropriate populations may include veterans with SUD and PTSD³⁹ and adolescents with marijuana dependence who use alcohol.⁴⁰

Safety and dosing. Suggested dosages for the treatment of alcohol use disorder based on these studies range from 1,000 to 2,400 mg/d (500 to 1,200 mg twice daily).

Clinical implications. Future work is needed to determine if NAC is effective for treating alcohol use disorders. Ongoing randomized clinical trials are examining the efficacy of NAC in reducing alcohol use among individuals with alcohol use disorder. It is premature to recommend NAC for treatment of alcohol use disorders.

Other psychiatric uses

Although we have highlighted NAC’s effect on glutamatergic transmission, evidence suggests that NAC may have multiple mechanisms of action that could impact psychiatric functioning. For example, NAC may also reverse oxidative stress, which is frequently observed in psychiatric disorders such as schizophrenia and bipolar disorder.^10,12 NAC also has anti-inflammatory properties. When inflammatory pathways of the CNS are dysregulated, production of neurotransmitters may be impaired, resulting in depression-like symptoms.^10,12,47 Preliminary evidence suggests that NAC may be effective in treating mood-related symptoms (eg, irritability, depression) in individuals with psychiatric disorders (eg, bipolar and depressive disorders, PTSD, and SUDs) and general symptoms of schizophrenia, obsessive-compulsive disorder, and trichotillomania, although mixed findings in controlled studies suggest a need for further research.^12,39

Continue to: NAC: A promising candidate

Initial evidence suggests NAC may be helpful for treating patients with SUDs. A patient seeking SUD treatment who is treated with NAC may experience a decreased drive, craving, or compulsion to use. Notably, NAC may be particularly useful in preventing relapse after an individual has achieved abstinence. Evidence suggests that NAC may be useful in the treatment of adults with cocaine use disorders who have achieved abstinence, and adolescents with cannabis use disorders. Preliminary results for adult tobacco use disorder are also promising. Human data examining the efficacy of NAC for alcohol use disorder is limited. Researchers’ ongoing challenge is to identify which patients with which SUDs are most likely to benefit from NAC, and to create clear clinical guidelines for the provider.

Bottom Line

N-acetylcysteine is likely to have modest effects for some patients who have a substance use disorder, particularly adults who use cocaine and adolescents who use marijuana. It may be useful in preventing relapse to substance use after an individual has achieved abstinence.

Related Resources

• Deepmala, Slattery J, Kumar N, et al. Clinical trials of N-acetylcysteine in psychiatry and neurology: a systematic review. Neurosci Biobehav Rev. 2015;55:294-321.
• Roberts-Wolfe D, Kalivas P. Glutamate transporter GLT-1 as a therapeutic target for substance use disorders. CNS Neurol Disord Drug Targets. 2015;14(6):745-756.
• National Institute on Drug Abuse. Treatment approaches for drug addiction. https://www.drugabuse.gov/publications/drugfacts/treatment-approaches-drug-addiction.

Drug Brand Names

Acamprosate • Campral
Acetaminophen • Tylenol
Baclofen • Lioresal
Bupropion • Zyban
Disulfiram • Antabuse
Naltrexone • Revia,Vivitrol
Varenicline • Chantix

Pharmacologic treatment options for many substance use disorders (SUDs) are limited. This is especially true for cocaine use disorder and cannabis use disorder, for which there are no FDA-approved medications. FDA-approved medications for other SUDs often take the form of replacement or agonist therapies (eg, nicotine replacement therapy) that substitute the effects of the substance to aid in cessation. Other pharmacotherapies treat symptoms of withdrawal, reduce craving, or provide aversive counter-conditioning if the patient consumes the substance while on the medication (eg, disulfiram).

The over-the-counter (OTC) antioxidant N-acetylcysteine (NAC) may be a potential treatment for SUDs. Although NAC is not approved by the FDA for treating SUDs, its proposed mechanism of action differs from that of current FDA-approved medications for SUDs. NAC’s potential for broad applicability, favorable adverse-effect profile, accessibility, and low cost make it an intriguing option for patients with multiple comorbidities, and potentially for individuals with polysubstance use. This article reviews the current evidence supporting NAC for treating SUDs, to provide insight about which patients may benefit from NAC and under which circumstances they are most likely to benefit.

NAC may correct glutamate dysregulation

Approximately 85% of individuals with an SUD do not seek treatment for it, and those who do are older, have a longer history of use, have more severe dependence, and have sought treatment numerous times before.¹ By the time most people seek treatment, years of chronic substance use have likely led to significant brain-related adaptations. Individuals with SUDs often indicate that their substance use began as a pleasurable activity—the effects of the drug were enjoyable and they were motivated to use it again. With repeated substance use, they may begin to develop a stronger urge to use the drug, driven not necessarily by a desire for pleasure, but by compulsion.²

Numerous neural adaptations underlie the transition from “liking” a substance to engaging in the compulsive use that is characteristic of an SUD.² For example, repeated use of an addictive substance may result in excess glutamate in the nucleus accumbens,^3,4 an area of the brain that plays a critical role in motivation and learning. As a result, it has been proposed that pharmacotherapies that help correct glutamate dysregulation may be effective in promoting abstinence or preventing relapse to a substance.^5,6

NAC may reverse the neural dysfunction seen in SUDs. As an OTC antioxidant that impacts glutamatergic functioning in the brain, NAC has long been used to treat acetaminophen overdose; however, in recent years, researchers have begun to tap its potential for treating substance use and psychiatric disorders. NAC is thought to upregulate the glutamate transporter (GLT-1) that removes excess glutamate from the nucleus accumbens.⁶ Several published reviews provide more in-depth information about the neurobiology of NAC.^6-10

The adverse-effect profile of NAC is relatively benign. Nausea, vomiting, diarrhea, and sleepiness are relatively infrequent and mild.^11,12 The bioavailability of NAC is about 4% to 9%, with an approximate half-life of 6.25 hours when orally administered.¹³ Because NAC is classified as an OTC supplement, the potency and preparation may vary by supplier. To maximize consistency, NAC should be obtained from a supplier that meets United States Pharmacopeia (USP) standards.

NAC for SUDs: Emerging evidence

Several recent reviews have described the efficacy of NAC for SUDs and other psychiatric disorders. Here we summarize the current research examining the efficacy of NAC for stimulant (ie, cocaine and methamphetamine), cannabis, tobacco, and alcohol use disorders.

Continue to: Stimulant use disorders

Stimulant use disorders. The United Nations Office for Drugs and Crime estimates that worldwide, more than 18 million people use cocaine and more than 35 million use amphetamines.¹⁴ There are currently no FDA-approved treatments for stimulant use disorders, and clinicians treating patients with cocaine or amphetamine dependence often are at a loss for how best to promote abstinence. Recent studies suggest that NAC may decrease drug-seeking behavior and cravings in adults who seek treatment. The results of studies examining NAC for treating cocaine use and methamphetamine use are summarized in Table 1^15-17 and Table 2,^18,19 respectively.

Cocaine cessation and relapse prevention. Several small pilot projects^15,16 found that compared with placebo, various doses of NAC reduced craving (as measured with a visual analog scale). However, in a double-blind, placebo-controlled study, NAC did not decrease cravings or use after 8 weeks of treatment in individuals with cocaine use disorder who were still using cocaine (ie, they had not yet become abstinent). Interestingly, those who were abstinent when treatment began reported lower craving and remained abstinent longer if they received NAC (vs placebo), which suggests that NAC may be useful for preventing relapse.¹⁷

Methamphetamine cessation and relapse prevention. One study (N = 32) that evaluated the use of NAC, 1,200 mg/d for 4 weeks, vs placebo found reduced cravings among methamphetamine users who were seeking treatment.¹⁸ In contrast, a study of 31 methamphetamine users who were not seeking treatment evaluated the use of NAC, 2,400 mg/d, plus naltrexone, 200 mg/d, vs placebo for 8 weeks.¹⁹ It found no significant differences in craving or use patterns. Further research is needed to optimize the use of NAC for stimulant use disorders, and to better understand the role that abstinence plays.

Appropriate populations. The most support for use of NAC has been as an anti-relapse agent in treatment-seeking adults.

Continue to: Safety and dosing

Safety and dosing. Suggested dosages for the treatment of cocaine use disorder range from 1,200 to 3,600 mg/d (typically 600 to 1,800 mg twice daily, due to NAC’s short half-life), with higher retention rates noted in individuals who received 2,400 mg/d and 3,600 mg/d.¹⁶

Clinical implications. NAC is thought to act as an anti-relapse agent, rather than an agent that can help someone who is actively using stimulants to stop. Consequently, NAC will likely be most helpful for patients who are motivated to quit and are abstinent when they start taking NAC; however, this hypothesis needs further testing.

Cannabis use disorder

There are no FDA-approved treatments for cannabis use disorder. Individuals who use marijuana or other forms of cannabis may be less likely to report negative consequences or seek treatment compared with those who use other substances. Approximately 9% of individuals who use marijuana develop cannabis use disorder²⁰; those who begin using marijuana earlier in adolescence are at increased risk.²¹ Commonly reported reasons for wanting to stop using marijuana include being concerned about health consequences, regaining or demonstrating self-control, saving money, avoiding legal consequences, obtaining or keeping employment, and reducing interpersonal conflict.^22,23 Table 3^24-27 summarizes initial evidence that suggests NAC may be particularly useful in reducing marijuana use among adolescents (age 15 to 21).^24,25

Cessation. An open-label, pilot clinical trial found significant reductions in self-reported marijuana use and craving—but not in biomarkers of use—among 24 adolescents after 4 weeks of NAC, 1,200 mg twice daily.²⁴ In an 8-week, double-blind, randomized controlled trial of 116 adolescents, NAC, 1,200 mg twice daily, plus contingency management doubled the odds of abstinence, but had no effect on self-reported craving or use.^25,26 In a sample of 302 adults, a 12-week trial of NAC, 1,200 mg twice daily, plus contingency management was no more effective than contingency management alone in promoting abstinence.²⁷

Continue to: Appropriate populations

Appropriate populations. Evidence is stronger for use of NAC among adolescents (age 15 to 21) than for individuals older than age 21.^25,27 Further research is needed to explore potential reasons for age-specific effects.

Safety and dosing. A safe and potentially efficacious dosage for the treatment of cannabis use disorder is 2,400 mg/d (1,200 mg twice daily).^24,25,27

Clinical implications. Combined with contingency management, NAC might be efficacious for adolescents with cannabis use disorder, with treatment gains evident by the fourth week of treatment.^24,25 To date, no clinical trials have examined the efficacy of NAC for treating cannabis use disorder without adjunctive contingency management, and research is needed to isolate the clinical effect of NAC among adolescents.

Tobacco use disorder

Cigarette smoking remains a leading cause of preventable death in the United States,²⁸ and nearly 70% of people who start using tobacco become dependent.²⁰ Existing FDA-approved treatments include nicotine replacement products, varenicline, and bupropion. Even though efficacious treatments exist, successful and sustained quit attempts are infrequent.²⁹ NAC may exert a complementary effect to existing tobacco cessation interventions, such as varenicline.³⁰ While these medications promote abstinence, NAC may be particularly beneficial in preventing relapse after abstinence has been achieved (Table 4^30-36).

Continue to: Cessation and relapse prevention

Cessation and relapse prevention. Several pilot studies found that adult smokers who received NAC (alone or in combination with another treatment) had lower carbon monoxide levels,^31,32 smoked fewer cigarettes,^32,33 and had fewer self-reported symptoms of nicotine dependence³⁴ and/or less craving for cigarettes.³¹ However, one study of 33 smokers did not find a reduction in craving or carbon monoxide for NAC compared with placebo.³³ Another pilot study of 22 young adult smokers found that those who received NAC rated their first cigarette after treatment (smoked in the laboratory) as less rewarding, relative to smokers who received a placebo.³⁵

Secondary analyses of adults with bipolar disorder³⁶ and adolescents with cannabis use disorder³⁷ found no decreases in tobacco use among those who received NAC compared with placebo. However, the studies in these analyses did not specifically recruit tobacco users, and participants who were tobacco users were not necessarily interested in quitting. This may partially explain discrepant findings.

Appropriate populations. NAC has been studied mostly in adult cigarette smokers.

Safety and dosing. Suggested dosages for treating tobacco use disorder range from 1,200 to 3,600 mg/d (600 to 1,800 mg twice daily).

Continue to: Clinical implications

Clinical implications. Data on NAC’s efficacy for tobacco use disorder come from small, pilot trials. Although initial evidence is promising, it is premature to suggest NAC for smoking cessation until a fully powered, randomized clinical trial provides evidence of efficacy.

Alcohol use disorder

Alcohol use disorders are widely prevalent; 13.9% of U.S. adults met criteria in the past year, and 29.1% of U.S. adults meet criteria in their lifetime.³⁸ Alcohol use disorders can result in significant negative consequences, including relationship problems, violent behavior, medical problems, and death. Existing FDA-approved medications for alcohol use disorder include naltrexone, acamprosate, and disulfiram.

Due to the severe potential health consequences of alcohol, NAC has been examined as a possible aid in preventing relapse. However, most studies have been conducted using animals. Three studies have examined alcohol use in humans (Table 5^36,39,40). One was a pilot study,³⁹ and the other 2 were secondary data analyses.^36,40 None of them specifically focused on alcohol use disorders. A pilot study of 35 veterans with co-occurring posttraumautic stress disorder (PTSD) and SUDs (82% of whom had an alcohol use disorder) found that compared with placebo, NAC significantly decreased PTSD symptoms, craving, and depression.³⁹ In a study of 75 adults with bipolar disorder, secondary alcohol use was not significantly reduced.³⁶ However, one study suggested that NAC may decrease adolescent alcohol and marijuana co-use.⁴⁰ Future work is needed to examine the potential clinical utility of NAC in individuals with alcohol use disorders.

Findings from animal studies indicate that NAC may:

• reduce alcohol-seeking⁴¹
• reduce withdrawal symptoms⁴²
• reduce the teratogenic effects of alcohol⁴³
• prevent alcohol toxicity⁴⁴
• reduce health-related consequences of alcohol (eg, myocardial oxidative stress⁴⁵ and alcohol-related steatohepatitis⁴⁶).

Continue to: Appropriate populations

Appropriate populations. Pilot studies have suggested that appropriate populations may include veterans with SUD and PTSD³⁹ and adolescents with marijuana dependence who use alcohol.⁴⁰

Safety and dosing. Suggested dosages for the treatment of alcohol use disorder based on these studies range from 1,000 to 2,400 mg/d (500 to 1,200 mg twice daily).

Clinical implications. Future work is needed to determine if NAC is effective for treating alcohol use disorders. Ongoing randomized clinical trials are examining the efficacy of NAC in reducing alcohol use among individuals with alcohol use disorder. It is premature to recommend NAC for treatment of alcohol use disorders.

Other psychiatric uses

Although we have highlighted NAC’s effect on glutamatergic transmission, evidence suggests that NAC may have multiple mechanisms of action that could impact psychiatric functioning. For example, NAC may also reverse oxidative stress, which is frequently observed in psychiatric disorders such as schizophrenia and bipolar disorder.^10,12 NAC also has anti-inflammatory properties. When inflammatory pathways of the CNS are dysregulated, production of neurotransmitters may be impaired, resulting in depression-like symptoms.^10,12,47 Preliminary evidence suggests that NAC may be effective in treating mood-related symptoms (eg, irritability, depression) in individuals with psychiatric disorders (eg, bipolar and depressive disorders, PTSD, and SUDs) and general symptoms of schizophrenia, obsessive-compulsive disorder, and trichotillomania, although mixed findings in controlled studies suggest a need for further research.^12,39

Continue to: NAC: A promising candidate

Initial evidence suggests NAC may be helpful for treating patients with SUDs. A patient seeking SUD treatment who is treated with NAC may experience a decreased drive, craving, or compulsion to use. Notably, NAC may be particularly useful in preventing relapse after an individual has achieved abstinence. Evidence suggests that NAC may be useful in the treatment of adults with cocaine use disorders who have achieved abstinence, and adolescents with cannabis use disorders. Preliminary results for adult tobacco use disorder are also promising. Human data examining the efficacy of NAC for alcohol use disorder is limited. Researchers’ ongoing challenge is to identify which patients with which SUDs are most likely to benefit from NAC, and to create clear clinical guidelines for the provider.

Bottom Line

N-acetylcysteine is likely to have modest effects for some patients who have a substance use disorder, particularly adults who use cocaine and adolescents who use marijuana. It may be useful in preventing relapse to substance use after an individual has achieved abstinence.

Related Resources

• Deepmala, Slattery J, Kumar N, et al. Clinical trials of N-acetylcysteine in psychiatry and neurology: a systematic review. Neurosci Biobehav Rev. 2015;55:294-321.
• Roberts-Wolfe D, Kalivas P. Glutamate transporter GLT-1 as a therapeutic target for substance use disorders. CNS Neurol Disord Drug Targets. 2015;14(6):745-756.
• National Institute on Drug Abuse. Treatment approaches for drug addiction. https://www.drugabuse.gov/publications/drugfacts/treatment-approaches-drug-addiction.

Drug Brand Names

Acamprosate • Campral
Acetaminophen • Tylenol
Baclofen • Lioresal
Bupropion • Zyban
Disulfiram • Antabuse
Naltrexone • Revia,Vivitrol
Varenicline • Chantix

Pharmacologic treatment options for many substance use disorders (SUDs) are limited. This is especially true for cocaine use disorder and cannabis use disorder, for which there are no FDA-approved medications. FDA-approved medications for other SUDs often take the form of replacement or agonist therapies (eg, nicotine replacement therapy) that substitute the effects of the substance to aid in cessation. Other pharmacotherapies treat symptoms of withdrawal, reduce craving, or provide aversive counter-conditioning if the patient consumes the substance while on the medication (eg, disulfiram).

The over-the-counter (OTC) antioxidant N-acetylcysteine (NAC) may be a potential treatment for SUDs. Although NAC is not approved by the FDA for treating SUDs, its proposed mechanism of action differs from that of current FDA-approved medications for SUDs. NAC’s potential for broad applicability, favorable adverse-effect profile, accessibility, and low cost make it an intriguing option for patients with multiple comorbidities, and potentially for individuals with polysubstance use. This article reviews the current evidence supporting NAC for treating SUDs, to provide insight about which patients may benefit from NAC and under which circumstances they are most likely to benefit.

NAC may correct glutamate dysregulation

Approximately 85% of individuals with an SUD do not seek treatment for it, and those who do are older, have a longer history of use, have more severe dependence, and have sought treatment numerous times before.¹ By the time most people seek treatment, years of chronic substance use have likely led to significant brain-related adaptations. Individuals with SUDs often indicate that their substance use began as a pleasurable activity—the effects of the drug were enjoyable and they were motivated to use it again. With repeated substance use, they may begin to develop a stronger urge to use the drug, driven not necessarily by a desire for pleasure, but by compulsion.²

Numerous neural adaptations underlie the transition from “liking” a substance to engaging in the compulsive use that is characteristic of an SUD.² For example, repeated use of an addictive substance may result in excess glutamate in the nucleus accumbens,^3,4 an area of the brain that plays a critical role in motivation and learning. As a result, it has been proposed that pharmacotherapies that help correct glutamate dysregulation may be effective in promoting abstinence or preventing relapse to a substance.^5,6

NAC may reverse the neural dysfunction seen in SUDs. As an OTC antioxidant that impacts glutamatergic functioning in the brain, NAC has long been used to treat acetaminophen overdose; however, in recent years, researchers have begun to tap its potential for treating substance use and psychiatric disorders. NAC is thought to upregulate the glutamate transporter (GLT-1) that removes excess glutamate from the nucleus accumbens.⁶ Several published reviews provide more in-depth information about the neurobiology of NAC.^6-10

The adverse-effect profile of NAC is relatively benign. Nausea, vomiting, diarrhea, and sleepiness are relatively infrequent and mild.^11,12 The bioavailability of NAC is about 4% to 9%, with an approximate half-life of 6.25 hours when orally administered.¹³ Because NAC is classified as an OTC supplement, the potency and preparation may vary by supplier. To maximize consistency, NAC should be obtained from a supplier that meets United States Pharmacopeia (USP) standards.

NAC for SUDs: Emerging evidence

Several recent reviews have described the efficacy of NAC for SUDs and other psychiatric disorders. Here we summarize the current research examining the efficacy of NAC for stimulant (ie, cocaine and methamphetamine), cannabis, tobacco, and alcohol use disorders.

Continue to: Stimulant use disorders

Stimulant use disorders. The United Nations Office for Drugs and Crime estimates that worldwide, more than 18 million people use cocaine and more than 35 million use amphetamines.¹⁴ There are currently no FDA-approved treatments for stimulant use disorders, and clinicians treating patients with cocaine or amphetamine dependence often are at a loss for how best to promote abstinence. Recent studies suggest that NAC may decrease drug-seeking behavior and cravings in adults who seek treatment. The results of studies examining NAC for treating cocaine use and methamphetamine use are summarized in Table 1^15-17 and Table 2,^18,19 respectively.

Cocaine cessation and relapse prevention. Several small pilot projects^15,16 found that compared with placebo, various doses of NAC reduced craving (as measured with a visual analog scale). However, in a double-blind, placebo-controlled study, NAC did not decrease cravings or use after 8 weeks of treatment in individuals with cocaine use disorder who were still using cocaine (ie, they had not yet become abstinent). Interestingly, those who were abstinent when treatment began reported lower craving and remained abstinent longer if they received NAC (vs placebo), which suggests that NAC may be useful for preventing relapse.¹⁷

Methamphetamine cessation and relapse prevention. One study (N = 32) that evaluated the use of NAC, 1,200 mg/d for 4 weeks, vs placebo found reduced cravings among methamphetamine users who were seeking treatment.¹⁸ In contrast, a study of 31 methamphetamine users who were not seeking treatment evaluated the use of NAC, 2,400 mg/d, plus naltrexone, 200 mg/d, vs placebo for 8 weeks.¹⁹ It found no significant differences in craving or use patterns. Further research is needed to optimize the use of NAC for stimulant use disorders, and to better understand the role that abstinence plays.

Appropriate populations. The most support for use of NAC has been as an anti-relapse agent in treatment-seeking adults.

Continue to: Safety and dosing

Safety and dosing. Suggested dosages for the treatment of cocaine use disorder range from 1,200 to 3,600 mg/d (typically 600 to 1,800 mg twice daily, due to NAC’s short half-life), with higher retention rates noted in individuals who received 2,400 mg/d and 3,600 mg/d.¹⁶

Clinical implications. NAC is thought to act as an anti-relapse agent, rather than an agent that can help someone who is actively using stimulants to stop. Consequently, NAC will likely be most helpful for patients who are motivated to quit and are abstinent when they start taking NAC; however, this hypothesis needs further testing.

Cannabis use disorder

There are no FDA-approved treatments for cannabis use disorder. Individuals who use marijuana or other forms of cannabis may be less likely to report negative consequences or seek treatment compared with those who use other substances. Approximately 9% of individuals who use marijuana develop cannabis use disorder²⁰; those who begin using marijuana earlier in adolescence are at increased risk.²¹ Commonly reported reasons for wanting to stop using marijuana include being concerned about health consequences, regaining or demonstrating self-control, saving money, avoiding legal consequences, obtaining or keeping employment, and reducing interpersonal conflict.^22,23 Table 3^24-27 summarizes initial evidence that suggests NAC may be particularly useful in reducing marijuana use among adolescents (age 15 to 21).^24,25

Cessation. An open-label, pilot clinical trial found significant reductions in self-reported marijuana use and craving—but not in biomarkers of use—among 24 adolescents after 4 weeks of NAC, 1,200 mg twice daily.²⁴ In an 8-week, double-blind, randomized controlled trial of 116 adolescents, NAC, 1,200 mg twice daily, plus contingency management doubled the odds of abstinence, but had no effect on self-reported craving or use.^25,26 In a sample of 302 adults, a 12-week trial of NAC, 1,200 mg twice daily, plus contingency management was no more effective than contingency management alone in promoting abstinence.²⁷

Continue to: Appropriate populations

Appropriate populations. Evidence is stronger for use of NAC among adolescents (age 15 to 21) than for individuals older than age 21.^25,27 Further research is needed to explore potential reasons for age-specific effects.

Safety and dosing. A safe and potentially efficacious dosage for the treatment of cannabis use disorder is 2,400 mg/d (1,200 mg twice daily).^24,25,27

Clinical implications. Combined with contingency management, NAC might be efficacious for adolescents with cannabis use disorder, with treatment gains evident by the fourth week of treatment.^24,25 To date, no clinical trials have examined the efficacy of NAC for treating cannabis use disorder without adjunctive contingency management, and research is needed to isolate the clinical effect of NAC among adolescents.

Tobacco use disorder

Cigarette smoking remains a leading cause of preventable death in the United States,²⁸ and nearly 70% of people who start using tobacco become dependent.²⁰ Existing FDA-approved treatments include nicotine replacement products, varenicline, and bupropion. Even though efficacious treatments exist, successful and sustained quit attempts are infrequent.²⁹ NAC may exert a complementary effect to existing tobacco cessation interventions, such as varenicline.³⁰ While these medications promote abstinence, NAC may be particularly beneficial in preventing relapse after abstinence has been achieved (Table 4^30-36).

Continue to: Cessation and relapse prevention

Cessation and relapse prevention. Several pilot studies found that adult smokers who received NAC (alone or in combination with another treatment) had lower carbon monoxide levels,^31,32 smoked fewer cigarettes,^32,33 and had fewer self-reported symptoms of nicotine dependence³⁴ and/or less craving for cigarettes.³¹ However, one study of 33 smokers did not find a reduction in craving or carbon monoxide for NAC compared with placebo.³³ Another pilot study of 22 young adult smokers found that those who received NAC rated their first cigarette after treatment (smoked in the laboratory) as less rewarding, relative to smokers who received a placebo.³⁵

Secondary analyses of adults with bipolar disorder³⁶ and adolescents with cannabis use disorder³⁷ found no decreases in tobacco use among those who received NAC compared with placebo. However, the studies in these analyses did not specifically recruit tobacco users, and participants who were tobacco users were not necessarily interested in quitting. This may partially explain discrepant findings.

Appropriate populations. NAC has been studied mostly in adult cigarette smokers.

Safety and dosing. Suggested dosages for treating tobacco use disorder range from 1,200 to 3,600 mg/d (600 to 1,800 mg twice daily).

Continue to: Clinical implications

Clinical implications. Data on NAC’s efficacy for tobacco use disorder come from small, pilot trials. Although initial evidence is promising, it is premature to suggest NAC for smoking cessation until a fully powered, randomized clinical trial provides evidence of efficacy.

Alcohol use disorder

Alcohol use disorders are widely prevalent; 13.9% of U.S. adults met criteria in the past year, and 29.1% of U.S. adults meet criteria in their lifetime.³⁸ Alcohol use disorders can result in significant negative consequences, including relationship problems, violent behavior, medical problems, and death. Existing FDA-approved medications for alcohol use disorder include naltrexone, acamprosate, and disulfiram.

Due to the severe potential health consequences of alcohol, NAC has been examined as a possible aid in preventing relapse. However, most studies have been conducted using animals. Three studies have examined alcohol use in humans (Table 5^36,39,40). One was a pilot study,³⁹ and the other 2 were secondary data analyses.^36,40 None of them specifically focused on alcohol use disorders. A pilot study of 35 veterans with co-occurring posttraumautic stress disorder (PTSD) and SUDs (82% of whom had an alcohol use disorder) found that compared with placebo, NAC significantly decreased PTSD symptoms, craving, and depression.³⁹ In a study of 75 adults with bipolar disorder, secondary alcohol use was not significantly reduced.³⁶ However, one study suggested that NAC may decrease adolescent alcohol and marijuana co-use.⁴⁰ Future work is needed to examine the potential clinical utility of NAC in individuals with alcohol use disorders.

Findings from animal studies indicate that NAC may:

• reduce alcohol-seeking⁴¹
• reduce withdrawal symptoms⁴²
• reduce the teratogenic effects of alcohol⁴³
• prevent alcohol toxicity⁴⁴
• reduce health-related consequences of alcohol (eg, myocardial oxidative stress⁴⁵ and alcohol-related steatohepatitis⁴⁶).

Continue to: Appropriate populations

Appropriate populations. Pilot studies have suggested that appropriate populations may include veterans with SUD and PTSD³⁹ and adolescents with marijuana dependence who use alcohol.⁴⁰

Safety and dosing. Suggested dosages for the treatment of alcohol use disorder based on these studies range from 1,000 to 2,400 mg/d (500 to 1,200 mg twice daily).

Clinical implications. Future work is needed to determine if NAC is effective for treating alcohol use disorders. Ongoing randomized clinical trials are examining the efficacy of NAC in reducing alcohol use among individuals with alcohol use disorder. It is premature to recommend NAC for treatment of alcohol use disorders.

Other psychiatric uses

Although we have highlighted NAC’s effect on glutamatergic transmission, evidence suggests that NAC may have multiple mechanisms of action that could impact psychiatric functioning. For example, NAC may also reverse oxidative stress, which is frequently observed in psychiatric disorders such as schizophrenia and bipolar disorder.^10,12 NAC also has anti-inflammatory properties. When inflammatory pathways of the CNS are dysregulated, production of neurotransmitters may be impaired, resulting in depression-like symptoms.^10,12,47 Preliminary evidence suggests that NAC may be effective in treating mood-related symptoms (eg, irritability, depression) in individuals with psychiatric disorders (eg, bipolar and depressive disorders, PTSD, and SUDs) and general symptoms of schizophrenia, obsessive-compulsive disorder, and trichotillomania, although mixed findings in controlled studies suggest a need for further research.^12,39

Continue to: NAC: A promising candidate

Initial evidence suggests NAC may be helpful for treating patients with SUDs. A patient seeking SUD treatment who is treated with NAC may experience a decreased drive, craving, or compulsion to use. Notably, NAC may be particularly useful in preventing relapse after an individual has achieved abstinence. Evidence suggests that NAC may be useful in the treatment of adults with cocaine use disorders who have achieved abstinence, and adolescents with cannabis use disorders. Preliminary results for adult tobacco use disorder are also promising. Human data examining the efficacy of NAC for alcohol use disorder is limited. Researchers’ ongoing challenge is to identify which patients with which SUDs are most likely to benefit from NAC, and to create clear clinical guidelines for the provider.

Bottom Line

N-acetylcysteine is likely to have modest effects for some patients who have a substance use disorder, particularly adults who use cocaine and adolescents who use marijuana. It may be useful in preventing relapse to substance use after an individual has achieved abstinence.

Related Resources

• Deepmala, Slattery J, Kumar N, et al. Clinical trials of N-acetylcysteine in psychiatry and neurology: a systematic review. Neurosci Biobehav Rev. 2015;55:294-321.
• Roberts-Wolfe D, Kalivas P. Glutamate transporter GLT-1 as a therapeutic target for substance use disorders. CNS Neurol Disord Drug Targets. 2015;14(6):745-756.
• National Institute on Drug Abuse. Treatment approaches for drug addiction. https://www.drugabuse.gov/publications/drugfacts/treatment-approaches-drug-addiction.

Drug Brand Names

Acamprosate • Campral
Acetaminophen • Tylenol
Baclofen • Lioresal
Bupropion • Zyban
Disulfiram • Antabuse
Naltrexone • Revia,Vivitrol
Varenicline • Chantix

The Centers for Medicare & Medicaid Services wants physician input on developing direct provider contracting models to cover Medicare beneficiaries.

Under a direct provider contracting (DPC) arrangement, Medicare could pay physicians or physician groups a monthly fee to deliver a specific set of services to beneficiaries, who would gain greater access to the physicians. The physicians would be accountable for those Medicare patients’ costs and care quality.

zimmytws/gettyimages

CMS is looking at how to incorporate this concept into the Medicare ranks. On April 23, CMS issued a request for information (RFI) seeking input across a wide range of topics, including provider/state participation, beneficiary participation, payment, general model design, program integrity and beneficiary protection, and how such models would fit within the existing accountable care organization framework.

The RFI offered one possible vision on how a direct provider contracting model could work.

“Under a primary care–focused DPC model, CMS could enter into arrangements with primary care practices under which CMS would pay these participating practices a fixed per beneficiary per month (PBPM) payment to cover the primary care services the practice would be expected to furnish under the model, which may include office visits, certain office-based procedures, and other non–visit-based services covered under the physician fee schedule, and flexibility in how otherwise billable services are delivered,” the RFI states.

Physicians could also earn performance bonuses, depending on how the DPC is structured, through “performance-based incentives for total cost of care and quality.”

CMS noted it also “could test ways to reduce administrative burden though innovative changes to claims submission processes for services included in the PBPM payment under these models.”

The direct provider contracting idea grew out of a previous RFI issued in 2017 by CMS’s Center for Medicare and Medicaid Innovation to collect ideas on new ways to deliver patient-centered care. The agency released the more than 1,000 comments received from that request on the same day it issued the RFI on direct provider contracting.

In those comments, a number of physician groups offered support for a direct-contracting approach.

For example, the American Academy of Family Physicians wrote that it “sees continued growth and interest in family physicians adopting this practice model in all settings types, including rural and underserved communities.” And the AAFP suggested that the innovation center should work with DPC organizations to learn more about them.

The American College of Physicians reiterated its previous position that it “supports physician and patient choice of practice and delivery models that are accessible, ethical, and viable and that strengthen the patient-physician relationship.” But the ACP raised a number of issues that could impede access to care or result in lower quality care.

The American Medical Association offered support for “testing of models in which physicians have the ability to deliver more or different services to patients who need them and to be paid more for doing so.”

The AMA suggested that some of the models to be tested include allowing patients to contract directly with physicians, with Medicare paying its fee schedule rates and patients paying the difference; allowing patients to receive their care from DPC practices and get reimbursed by Medicare; or allowing “physicians to define a team of providers who will provide all of the treatment needed for an acute condition or management of a chronic condition, and then allowing patients who select the team to receive all of the services related to their condition from the team in return for a single predefined cost-sharing amount.”

Comments on the RFI are due May 25.

[email protected]

The Centers for Medicare & Medicaid Services wants physician input on developing direct provider contracting models to cover Medicare beneficiaries.

Under a direct provider contracting (DPC) arrangement, Medicare could pay physicians or physician groups a monthly fee to deliver a specific set of services to beneficiaries, who would gain greater access to the physicians. The physicians would be accountable for those Medicare patients’ costs and care quality.

zimmytws/gettyimages

CMS is looking at how to incorporate this concept into the Medicare ranks. On April 23, CMS issued a request for information (RFI) seeking input across a wide range of topics, including provider/state participation, beneficiary participation, payment, general model design, program integrity and beneficiary protection, and how such models would fit within the existing accountable care organization framework.

The RFI offered one possible vision on how a direct provider contracting model could work.

“Under a primary care–focused DPC model, CMS could enter into arrangements with primary care practices under which CMS would pay these participating practices a fixed per beneficiary per month (PBPM) payment to cover the primary care services the practice would be expected to furnish under the model, which may include office visits, certain office-based procedures, and other non–visit-based services covered under the physician fee schedule, and flexibility in how otherwise billable services are delivered,” the RFI states.

Physicians could also earn performance bonuses, depending on how the DPC is structured, through “performance-based incentives for total cost of care and quality.”

CMS noted it also “could test ways to reduce administrative burden though innovative changes to claims submission processes for services included in the PBPM payment under these models.”

The direct provider contracting idea grew out of a previous RFI issued in 2017 by CMS’s Center for Medicare and Medicaid Innovation to collect ideas on new ways to deliver patient-centered care. The agency released the more than 1,000 comments received from that request on the same day it issued the RFI on direct provider contracting.

In those comments, a number of physician groups offered support for a direct-contracting approach.

For example, the American Academy of Family Physicians wrote that it “sees continued growth and interest in family physicians adopting this practice model in all settings types, including rural and underserved communities.” And the AAFP suggested that the innovation center should work with DPC organizations to learn more about them.

The American College of Physicians reiterated its previous position that it “supports physician and patient choice of practice and delivery models that are accessible, ethical, and viable and that strengthen the patient-physician relationship.” But the ACP raised a number of issues that could impede access to care or result in lower quality care.

The American Medical Association offered support for “testing of models in which physicians have the ability to deliver more or different services to patients who need them and to be paid more for doing so.”

The AMA suggested that some of the models to be tested include allowing patients to contract directly with physicians, with Medicare paying its fee schedule rates and patients paying the difference; allowing patients to receive their care from DPC practices and get reimbursed by Medicare; or allowing “physicians to define a team of providers who will provide all of the treatment needed for an acute condition or management of a chronic condition, and then allowing patients who select the team to receive all of the services related to their condition from the team in return for a single predefined cost-sharing amount.”

Comments on the RFI are due May 25.

[email protected]

The Centers for Medicare & Medicaid Services wants physician input on developing direct provider contracting models to cover Medicare beneficiaries.

Under a direct provider contracting (DPC) arrangement, Medicare could pay physicians or physician groups a monthly fee to deliver a specific set of services to beneficiaries, who would gain greater access to the physicians. The physicians would be accountable for those Medicare patients’ costs and care quality.

zimmytws/gettyimages

CMS is looking at how to incorporate this concept into the Medicare ranks. On April 23, CMS issued a request for information (RFI) seeking input across a wide range of topics, including provider/state participation, beneficiary participation, payment, general model design, program integrity and beneficiary protection, and how such models would fit within the existing accountable care organization framework.

The RFI offered one possible vision on how a direct provider contracting model could work.

“Under a primary care–focused DPC model, CMS could enter into arrangements with primary care practices under which CMS would pay these participating practices a fixed per beneficiary per month (PBPM) payment to cover the primary care services the practice would be expected to furnish under the model, which may include office visits, certain office-based procedures, and other non–visit-based services covered under the physician fee schedule, and flexibility in how otherwise billable services are delivered,” the RFI states.

Physicians could also earn performance bonuses, depending on how the DPC is structured, through “performance-based incentives for total cost of care and quality.”

CMS noted it also “could test ways to reduce administrative burden though innovative changes to claims submission processes for services included in the PBPM payment under these models.”

The direct provider contracting idea grew out of a previous RFI issued in 2017 by CMS’s Center for Medicare and Medicaid Innovation to collect ideas on new ways to deliver patient-centered care. The agency released the more than 1,000 comments received from that request on the same day it issued the RFI on direct provider contracting.

In those comments, a number of physician groups offered support for a direct-contracting approach.

For example, the American Academy of Family Physicians wrote that it “sees continued growth and interest in family physicians adopting this practice model in all settings types, including rural and underserved communities.” And the AAFP suggested that the innovation center should work with DPC organizations to learn more about them.

The American College of Physicians reiterated its previous position that it “supports physician and patient choice of practice and delivery models that are accessible, ethical, and viable and that strengthen the patient-physician relationship.” But the ACP raised a number of issues that could impede access to care or result in lower quality care.

The American Medical Association offered support for “testing of models in which physicians have the ability to deliver more or different services to patients who need them and to be paid more for doing so.”

The AMA suggested that some of the models to be tested include allowing patients to contract directly with physicians, with Medicare paying its fee schedule rates and patients paying the difference; allowing patients to receive their care from DPC practices and get reimbursed by Medicare; or allowing “physicians to define a team of providers who will provide all of the treatment needed for an acute condition or management of a chronic condition, and then allowing patients who select the team to receive all of the services related to their condition from the team in return for a single predefined cost-sharing amount.”

Comments on the RFI are due May 25.

[email protected]

A 71-year-old woman is brought to the emergency department by her neighbor after complaining of fatigue and light-headedness for the last 8 hours. The patient lives alone and was feeling well when she woke up this morning, but then began to feel nauseated and vomited twice.

The patient appears drowsy and confused and cannot provide any further history. Her medical records show that she was seen in the cardiology clinic 6 months ago but has not kept her appointments since then.

Her medical history includes atrial fibrillation, hypertension, type 2 diabetes mellitus, and osteoarthritis. Her medications are daily warfarin, atenolol, aspirin, candesartan, and metformin, and she takes acetaminophen as needed. She is neither a smoker nor a drug user, but she drinks alcohol occasionally. Her family history is significant for her mother’s death from breast cancer at age 55.

The neighbor confirms that the patient appeared well this morning and has not had any recent illnesses except for a minor cold last week that improved over 5 days with acetaminophen only.

INITIAL EVALUATION AND MANAGEMENT

Physical examination

On physical examination, her blood pressure is 80/40 mm Hg, respiratory rate 25 breaths per minute, oral temperature 38.3°C (100.9°F), and heart rate 130 beats per minute and irregular.

Her neck veins are flat, and her chest is clear to auscultation with normal heart sounds. Abdominal palpation elicits discomfort in the middle segments, voluntary withdrawal, and abdominal wall rigidity. Her skin feels dry and cool, with decreased turgor.

Initial treatment

The patient is given 1 L of 0.9% saline intravenously over the first hour and then is transferred to the intensive care unit, where a norepinephrine drip is started to treat her ongoing hypotension. Normal saline is continued at a rate of 500 mL per hour for the next 4 hours.

Cardiac monitoring and 12-lead electrocardiography show atrial fibrillation with a rapid ventricular response of 138 beats per minute, but electrical cardioversion is not done.

Initial laboratory tests

Of note, her international normalized ratio (INR) is 6.13, while the therapeutic range for a patient taking warfarin because of atrial fibrillation is 2.0 to 3.0.

Her blood pH is 7.34 (reference range 7.35–7.45), and her bicarbonate level is 18 mmol/L (22–26); a low pH and low bicarbonate together indicate metabolic acidosis. Her sodium level is 128 mmol/L (135–145), her chloride level is 100 mmol/L (97–107), and, as mentioned, her bicarbonate level is 18 mmol/L; therefore, her anion gap is 128 – (100 + 18) = 10 mmol/L, which is normal (≤ 10).¹

Her serum creatinine level is 1.3 mg/dL (0.5–1.1), and her blood urea nitrogen level is 35 mg/dL (7–20).

Her potassium level is 5.8 mmol/L, which is consistent with hyperkalemia (reference range 3.5–5.2).

DIFFERENTIAL DIAGNOSIS

1. Which of the following is the most likely cause of this patient’s symptoms?

• Adrenal crisis
• Cardiogenic shock due to decreased cardiac contractility
• Intracranial hemorrhage
• Acute abdomen due to small bowel obstruction
• Septic shock due to bacterial toxin-induced loss of vascular tone

Our patient is presenting with shock. Given our inability to obtain a meaningful history, the differential diagnosis is broad and includes all of the above.

Adrenal crisis

The sudden onset and laboratory results that include hyperkalemia, hyponatremia, and normal anion gap metabolic acidosis raise suspicion of adrenal crisis resulting in acute mineralocorticoid and glucocorticoid insufficiency.¹

The patient’s elevated serum creatinine and high blood urea nitrogen-to-creatinine ratio of 26.9 (reference range 10–20) also suggest intravascular volume contraction. Her low hemoglobin level and supratherapeutic INR, possibly due to an interaction between warfarin and acetaminophen combined with poor medical follow-up, raise suspicion of acute bilateral adrenal necrosis due to hemorrhage.

Bilateral adrenal hemorrhage is one cause of adrenal crisis resulting in bilateral adrenal necrosis. Risk factors for adrenal hemorrhage include anticoagulation therapy, underlying coagulopathy, postoperative states, and certain infections such as meningococcemia and Haemophilus influenzae infection.^2–5 Nevertheless, in most cases the INR is in the therapeutic range and the patient has no bleeding elsewhere.⁴ Other causes of adrenal necrosis include emboli, sepsis, and blunt trauma.^6,7

Other causes of adrenal crisis are listed in Table 3.

Cardiogenic shock

Intracranial hemorrhage can present with a decreased level of consciousness, but it is less likely to cause hypotension, as the cranial space is limited. If massive intracranial hemorrhage would occur, the increase in intracranial pressure would more likely cause hypertension by the Cushing reflex than hypotension.

Acute abdomen

Abdominal pain and rigidity along with fever can be presenting symptoms of both adrenal insufficiency and an acute abdomen due to intestinal obstruction.⁴ However, intestinal obstruction typically causes a high anion gap metabolic acidosis due to lactic acidosis, instead of the normal anion gap metabolic acidosis present in this patient.⁸ Moreover, her deranged electrolytes, supratherapeutic INR, and absence of previous gastroenterologic conditions make adrenal crisis a more likely diagnosis.

Septic shock

Septic shock would also cause fever and hypotension as bacterial toxins induce a pyrexic response and vasodilation. However, at such an early stage of sepsis, the patient would be expected to be warm and hyperemic, whereas this patient’s skin is cool and dry due to volume depletion secondary to adrenal insufficiency.⁹ Sepsis would also cause a high anion gap metabolic acidosis due to lactic acidosis, as opposed to this patient’s normal anion gap metabolic acidosis. These findings, along with the metabolic derangements and the absence of a focus of infection, make sepsis a less likely possibility.

CASE CONTINUED: CARDIOMEGALY, PERSISTENT HYPOTENSION

Blood is drawn for cultures and measurement of troponins and lactic acid, and urine samples are taken for culture and biochemical analysis. Chest radiography shows mild cardiomegaly. The patient is started empirically on vancomycin and cefepime, and her warfarin is discontinued.

Five hours after presenting to the emergency department, her blood pressure remains at 80/40 mm Hg even after receiving 3 L of normal saline intravenously.

PROMPT MANAGEMENT OF ADRENAL CRISIS

2. Which of the following is the most appropriate next step in managing this patient?

• Draw samples for serum cortisol and plasma adrenocorticotropic hormone (ACTH) levels, then give hydrocortisone 100 mg intravenously
• Perform abdominal computed tomography (CT) without contrast
• Perform transthoracic echocardiography
• Increase the norepinephrine infusion
• Immediately give fludrocortisone

First give fluids

The first step in managing a patient with suspected adrenal crisis is liberal intravenous fluid administration to replenish the depleted intravascular space. The amount and choice of fluid is empiric, but a recommendation is 1 L of normal saline or dextrose 5% in normal saline, infused quickly over the first hour and then titrated according to the patient’s fluid status.¹⁰

Measure cortisol and ACTH; start corticosteroids immediately

Immediate therapy with an appropriate stress dose of intravenous corticosteroids (eg, hydrocortisone 100 mg) is essential. However, this should be done after drawing blood for cortisol and ACTH measurements.¹⁰

Do not delay corticosteroid therapy while awaiting the results of the diagnostic tests.

In addition, in the early phase of evolving primary adrenal insufficiency, measurement of plasma renin and aldosterone levels may be beneficial, as mineralocorticoid deficiency may predominate.^10,12,13

One of the most important aims of early corticosteroid supplementation is to prevent further hyponatremia by reducing a reactive increase in antidiuretic hormone secretion caused by cortisol deficiency. Corticosteroids also help to restore normal blood pressure by increasing vascular tone, as glucocorticoid receptor activation potentiates the vasoconstrictor actions of norepinephrine, angiotensin II, and other vasoconstrictors.^14,15

Which corticosteroid to use?

Which corticosteroid to use in previously undiagnosed adrenal insufficiency is controversial. The Endocrine Society¹⁰ and Japan Endocrine Society¹⁶ clinical practice guidelines recommend hydrocortisone in a 100-mg intravenous bolus followed by 200 mg over 24 hours.

The choice of hydrocortisone is justified by its superior mineralocorticoid activity.^10,16 Further, hydrocortisone is preferred over dexamethasone if the patient is known to have primary adrenal insufficiency, or if the serum potassium level is higher than 6.0 mmol/L.

Some clinicians, on the other hand, recommend dexamethasone, given as a 4-mg intravenous bolus followed by 4-mg boluses every 12 hours. Their rationale is that dexamethasone, unlike hydrocortisone, does not interfere with subsequent serum cortisol assays if the patient later undergoes ACTH stimulation testing.¹⁷ Dexamethasone may also be preferred to minimize unwanted mineralocorticoid effects, such as in neurosurgical patients at risk of brain edema.

If hydrocortisone is used, ACTH stimulation testing can be done after withholding hydrocortisone for 24 hours once the patient is stable. (It should be restarted after the test if the results are abnormal.)

Abdominal CT should be done in our patient to address the possibility of bilateral adrenal hemorrhage. However, it is preferable to wait until the patient is stabilized.

Echocardiography. Our patient is likely to have an element of cardiac failure, given her hypertension and cardiomegaly. However, decompensated heart failure is probably not the cause of her presentation. Thus, the first priority is to treat her adrenal crisis, and echocardiography should be deferred.

Increasing the norepinephrine infusion is unlikely to improve her blood pressure very much, as she is significantly volume-depleted. Further, low cortisol decreases the vascular response to norepinephrine.¹⁵

Mineralocorticoids such as fludrocortisone are used to treat primary adrenal insufficiency. However, they are not required during acute management of adrenal crisis, as 40 mg of hydrocortisone offers mineralocorticoid activity equivalent to 100 µg of fludrocortisone. Thus, the high doses of hydrocortisone used to treat adrenal crisis provide adequate mineralocorticoid therapy.^10,18

If dexamethasone is used, its effect along with normal saline supplementation would be sufficient to replete the intravenous space and bring the sodium level back up to normal in the acute setting.

CASE RESUMED: IMPROVEMENT WITH HYDROCORTISONE

The patient’s blood is drawn for serum cortisol and plasma ACTH measurements. A 100-mg intravenous bolus of hydrocortisone is given, followed by a 50-mg bolus every 6 hours until the patient stabilizes.

Twenty-four hours later, the patient states that she has more energy, and her appetite has improved. The norepinephrine infusion is stopped 48 hours after presentation, at which time her blood pressure is 120/70 mm Hg, heart rate 85 beats per minute and irregular, and temperature 36.7°C (98.1°F). Her current laboratory values include the following:

• Serum sodium 137 mmolL
• Serum potassium 4.3 mmol/L
• Hemoglobin 9.3 g/dL
• Serum cortisol (random) 7.2 μg/dL
• Plasma ACTH 752 pg/mL (10–60 pg/mL).

ESTABLISHING THE DIAGNOSIS OF ADRENAL INSUFFICIENCY

3. Which of the following is the most appropriate test to establish the diagnosis of adrenal insufficiency?

• 7 am total serum cortisol measurement
• Random serum cortisol measurement
• 7 am salivary cortisol measurement
• 24-hour urinary free cortisol measurement
• ACTH stimulation test for cortisol
• Insulin tolerance test for cortisol

These tests also help determine the type of adrenal insufficiency (primary, secondary, or tertiary) and guide further management. Secondary adrenal insufficiency is caused by inadequate pituitary ACTH secretion and subsequent inadequate cortisol production, whereas tertiary adrenal insufficiency is caused by inadequate hypothalamic corticotropin-releasing hormone secretion and subsequent inadequate ACTH and cortisol production. The diagnosis of adrenal insufficiency relies first on demonstrating inappropriately low total serum cortisol production. Subsequently, serum ACTH helps to differentiate between primary (high ACTH) and secondary or tertiary (low or inappropriately normal ACTH) adrenal insufficiency.

Each test listed above may demonstrate a low cortisol level. However, in a nonacute setting, safety concerns (especially regarding insulin tolerance testing), poor diagnostic value, feasibility (ie, the difficulty of 24-hour tests), and poor sensitivity of 7 am cortisol make the ACTH stimulation test the most appropriate test in clinical practice to establish the diagnosis of adrenal insufficiency.

7 am serum cortisol measurement

Measuring the serum cortisol level early in the morning in the nonacute setting could be of diagnostic value, as an extremely low value (< 3–5 μg/dL) is almost 100% specific for adrenal insufficiency in the absence of concurrent exogenous steroid intake. However, the very low cutoff for this test causes poor sensitivity (about 33%), as many patients have partial adrenal insufficiency and hence have higher serum cortisol levels that may even be in the normal physiologic range.^19–22

Random serum cortisol measurements

Random serum cortisol measurements are not very useful in a nonacute setting, since cortisol levels are affected by factors such as stress and hydration status. Moreover, they fluctuate during the day in a circadian rhythm.

On the other hand, random serum cortisol is a very good test to evaluate for adrenal insufficiency in the acute setting. A random value higher than 15 to 18 μg/dL is almost always associated with adequate adrenal function and generally rules out adrenal insufficiency.^11,23,24

The same principle applies to early morning salivary cortisol. Only extremely low values (< 2.65 ng/mL) may distinguish patients with adrenal insufficiency from healthy individuals, with 97.1% sensitivity and 93.3% specificity.²⁵

Of note, early morning salivary cortisol is not routinely measured in most clinical practices for evaluation of adrenal function. Hence, morning serum and morning salivary cortisol are useful screening tools and have meaningful results when their values are in the extremes of the spectrum, but they are not reliable as a single test, as they may overlook patients with partial adrenal insufficiency.

Urinary cortisol measurement

Urinary cortisol measurement is not used to diagnose adrenal insufficiency, as values can be normal in patients with partial adrenal insufficiency.

The ACTH stimulation test

The ACTH stimulation test involves an intramuscular or intravenous injection of cosyntropin (a synthetic analogue of ACTH fragment 1–24 that has the full activity of native ACTH) and measuring total serum cortisol at baseline, 30 minutes, and 60 minutes to assess the response of the adrenal glands.

The test can be done using a high or low dose of cosyntropin. The Endocrine Society’s 2016 guidelines recommend the high dose (250 μg) for most patients.¹⁰ The standard high-dose stimulation test can be done at any time during the day.²⁶ If the cosyntropin is injected intravenously, any value higher than 18 to 20 μg/dL indicates normal adrenal function and excludes adrenal insufficiency.^27,28 If intramuscular injection is used, any value higher than 16 to 18 μg/dL at 30 minutes post-consyntropin excludes adrenal insufficiency.²⁹

The ACTH stimulation test may not exclude acute secondary or tertiary adrenal insufficiency.

Insulin tolerance testing

Insulin tolerance testing remains the gold standard for diagnosing adrenal insufficiency and assessing the integrity of the pituitary-adrenal axis. However, given its difficulty to perform, safety concerns, and the availability of other reliable tests, its use in clinical practice is limited. It is nonetheless useful in assessing patients with recent onset of ACTH deficiency.^30,31

CASE RESUMED: PATIENT DISCHARGED, LOST TO FOLLOW-UP

Abdominal CT without contrast is done and demonstrates bilateral adrenal hemorrhage. Thus, the patient is diagnosed with primary acute adrenal insufficiency due to adrenal necrosis.

She is started on oral hydrocortisone and fludrocortisone after intravenous hydrocortisone is discontinued. She is counseled about adhering to medications, wearing a medical alert bracelet, giving herself emergency cortisol injections, taking higher doses of hydrocortisone if she is ill, and monitoring her INR. She is discharged home after her symptoms resolve.

The patient does not keep her scheduled appointment and is lost to follow-up. She returns 2 years later complaining of fatigue and feeling unwell. She admits that she stopped taking hydrocortisone 1 year ago after reading an online article about corticosteroid side effects. She has continued to take fludrocortisone.

MINERALOCORTICOID VS CORTICOSTEROID DEFICIENCY

4. Which of the following is least likely to be present in this patient at this time?

• Intravascular volume depletion
• Hyponatremia
• Skin hyperpigmentation
• Normokalemia
• Elevated serum ACTH level

Intravascular volume depletion

Intravascular volume depletion is the least likely to be present. This is because intravascular volume depletion is mainly secondary to mineralocorticoid deficiency rather than corticosteroid deficiency, which is not present in this patient, as she is compliant with her mineralocorticoid replacement therapy.^32,33 However, even with sufficient mineralocorticoid replacement, mild hypotension may be present in this patient due to corticosteroid deficiency-induced loss of vascular tone.

Hyponatremia

Hyponatremia in adrenal insufficiency is not due only to mineralocorticoid deficiency. Patients with secondary or tertiary adrenal insufficiency may also exhibit hyponatremia.³⁴ ACTH deficiency in such patients is not expected to cause mineralocorticoid deficiency, as ACTH has only a minor role in aldosterone production.

It has been proposed that hyponatremia in secondary adrenal insufficiency is due to cortisol deficiency resulting in an increase of antidiuretic hormone secretion.^35,36 The mechanisms for increased antidiuretic hormone include cortisol deficiency resulting in an increased corticotropin-releasing hormone level, which acts as an antidiuretic hormone secretagogue,^37,38 and cortisol directly suppressing antidiuretic hormone secretion.³⁹

In our patient, volume expansion and hyponatremia are expected due to increased antidiuretic hormone secretion as a result of corticosteroid insufficiency.

Hyperpigmentation of the skin is present only in long-standing primary adrenal insufficiency. This is due to chronic cortisol deficiency causing an increased secretion of pro-opiomelanocortin, a prohormone that is cleaved into ACTH, melanocyte-stimulating hormone, and other hormones. Melanocyte-stimulating hormone causes skin hyperpigmentation due to increased melanin synthesis.⁴⁰ The hyperpigmentation is seen in sun-exposed areas, pressure areas, palmar creases, nipples, and mucous membranes.

This patient has long-standing corticosteroid deficiency due to noncompliance and primary adrenal insufficiency, and as a result she is expected to have elevated serum ACTH and hyperpigmentation.

Normokalemia

Mineralocorticoid deficiency results in hyperkalemia and metabolic acidosis by impairing renal excretion of potassium and acid.⁴¹ This patient is compliant with her mineralocorticoid replacement regimen; thus, potassium levels and pH are expected to be normal.

TAKE-HOME POINTS

• Suspect adrenal crisis in any patient who presents with shock.
• Acute abdomen or unexplained fever could be among the manifestations.
• Initial management requires liberal normal saline intravenous fluid administration to replete the intravascular space.
• Draw blood samples for serum chemistry, cortisol, and ACTH, followed immediately by intravenous hydrocortisone supplementation.
• In critically ill patients, evaluate adrenal function with random serum cortisol; in a nonacute setting use the ACTH stimulation test.
• Chronic management of primary adrenal insufficiency requires corticosteroid and mineralocorticoid therapy.

A 71-year-old woman is brought to the emergency department by her neighbor after complaining of fatigue and light-headedness for the last 8 hours. The patient lives alone and was feeling well when she woke up this morning, but then began to feel nauseated and vomited twice.

The patient appears drowsy and confused and cannot provide any further history. Her medical records show that she was seen in the cardiology clinic 6 months ago but has not kept her appointments since then.

Her medical history includes atrial fibrillation, hypertension, type 2 diabetes mellitus, and osteoarthritis. Her medications are daily warfarin, atenolol, aspirin, candesartan, and metformin, and she takes acetaminophen as needed. She is neither a smoker nor a drug user, but she drinks alcohol occasionally. Her family history is significant for her mother’s death from breast cancer at age 55.

The neighbor confirms that the patient appeared well this morning and has not had any recent illnesses except for a minor cold last week that improved over 5 days with acetaminophen only.

INITIAL EVALUATION AND MANAGEMENT

Physical examination

On physical examination, her blood pressure is 80/40 mm Hg, respiratory rate 25 breaths per minute, oral temperature 38.3°C (100.9°F), and heart rate 130 beats per minute and irregular.

Her neck veins are flat, and her chest is clear to auscultation with normal heart sounds. Abdominal palpation elicits discomfort in the middle segments, voluntary withdrawal, and abdominal wall rigidity. Her skin feels dry and cool, with decreased turgor.

Initial treatment

The patient is given 1 L of 0.9% saline intravenously over the first hour and then is transferred to the intensive care unit, where a norepinephrine drip is started to treat her ongoing hypotension. Normal saline is continued at a rate of 500 mL per hour for the next 4 hours.

Cardiac monitoring and 12-lead electrocardiography show atrial fibrillation with a rapid ventricular response of 138 beats per minute, but electrical cardioversion is not done.

Initial laboratory tests

Of note, her international normalized ratio (INR) is 6.13, while the therapeutic range for a patient taking warfarin because of atrial fibrillation is 2.0 to 3.0.

Her blood pH is 7.34 (reference range 7.35–7.45), and her bicarbonate level is 18 mmol/L (22–26); a low pH and low bicarbonate together indicate metabolic acidosis. Her sodium level is 128 mmol/L (135–145), her chloride level is 100 mmol/L (97–107), and, as mentioned, her bicarbonate level is 18 mmol/L; therefore, her anion gap is 128 – (100 + 18) = 10 mmol/L, which is normal (≤ 10).¹

Her serum creatinine level is 1.3 mg/dL (0.5–1.1), and her blood urea nitrogen level is 35 mg/dL (7–20).

Her potassium level is 5.8 mmol/L, which is consistent with hyperkalemia (reference range 3.5–5.2).

DIFFERENTIAL DIAGNOSIS

1. Which of the following is the most likely cause of this patient’s symptoms?

• Adrenal crisis
• Cardiogenic shock due to decreased cardiac contractility
• Intracranial hemorrhage
• Acute abdomen due to small bowel obstruction
• Septic shock due to bacterial toxin-induced loss of vascular tone

Our patient is presenting with shock. Given our inability to obtain a meaningful history, the differential diagnosis is broad and includes all of the above.

Adrenal crisis

The sudden onset and laboratory results that include hyperkalemia, hyponatremia, and normal anion gap metabolic acidosis raise suspicion of adrenal crisis resulting in acute mineralocorticoid and glucocorticoid insufficiency.¹

The patient’s elevated serum creatinine and high blood urea nitrogen-to-creatinine ratio of 26.9 (reference range 10–20) also suggest intravascular volume contraction. Her low hemoglobin level and supratherapeutic INR, possibly due to an interaction between warfarin and acetaminophen combined with poor medical follow-up, raise suspicion of acute bilateral adrenal necrosis due to hemorrhage.

Bilateral adrenal hemorrhage is one cause of adrenal crisis resulting in bilateral adrenal necrosis. Risk factors for adrenal hemorrhage include anticoagulation therapy, underlying coagulopathy, postoperative states, and certain infections such as meningococcemia and Haemophilus influenzae infection.^2–5 Nevertheless, in most cases the INR is in the therapeutic range and the patient has no bleeding elsewhere.⁴ Other causes of adrenal necrosis include emboli, sepsis, and blunt trauma.^6,7

Other causes of adrenal crisis are listed in Table 3.

Cardiogenic shock

Intracranial hemorrhage can present with a decreased level of consciousness, but it is less likely to cause hypotension, as the cranial space is limited. If massive intracranial hemorrhage would occur, the increase in intracranial pressure would more likely cause hypertension by the Cushing reflex than hypotension.

Acute abdomen

Abdominal pain and rigidity along with fever can be presenting symptoms of both adrenal insufficiency and an acute abdomen due to intestinal obstruction.⁴ However, intestinal obstruction typically causes a high anion gap metabolic acidosis due to lactic acidosis, instead of the normal anion gap metabolic acidosis present in this patient.⁸ Moreover, her deranged electrolytes, supratherapeutic INR, and absence of previous gastroenterologic conditions make adrenal crisis a more likely diagnosis.

Septic shock

Septic shock would also cause fever and hypotension as bacterial toxins induce a pyrexic response and vasodilation. However, at such an early stage of sepsis, the patient would be expected to be warm and hyperemic, whereas this patient’s skin is cool and dry due to volume depletion secondary to adrenal insufficiency.⁹ Sepsis would also cause a high anion gap metabolic acidosis due to lactic acidosis, as opposed to this patient’s normal anion gap metabolic acidosis. These findings, along with the metabolic derangements and the absence of a focus of infection, make sepsis a less likely possibility.

CASE CONTINUED: CARDIOMEGALY, PERSISTENT HYPOTENSION

Blood is drawn for cultures and measurement of troponins and lactic acid, and urine samples are taken for culture and biochemical analysis. Chest radiography shows mild cardiomegaly. The patient is started empirically on vancomycin and cefepime, and her warfarin is discontinued.

Five hours after presenting to the emergency department, her blood pressure remains at 80/40 mm Hg even after receiving 3 L of normal saline intravenously.

PROMPT MANAGEMENT OF ADRENAL CRISIS

2. Which of the following is the most appropriate next step in managing this patient?

• Draw samples for serum cortisol and plasma adrenocorticotropic hormone (ACTH) levels, then give hydrocortisone 100 mg intravenously
• Perform abdominal computed tomography (CT) without contrast
• Perform transthoracic echocardiography
• Increase the norepinephrine infusion
• Immediately give fludrocortisone

First give fluids

The first step in managing a patient with suspected adrenal crisis is liberal intravenous fluid administration to replenish the depleted intravascular space. The amount and choice of fluid is empiric, but a recommendation is 1 L of normal saline or dextrose 5% in normal saline, infused quickly over the first hour and then titrated according to the patient’s fluid status.¹⁰

Measure cortisol and ACTH; start corticosteroids immediately

Immediate therapy with an appropriate stress dose of intravenous corticosteroids (eg, hydrocortisone 100 mg) is essential. However, this should be done after drawing blood for cortisol and ACTH measurements.¹⁰

Do not delay corticosteroid therapy while awaiting the results of the diagnostic tests.

In addition, in the early phase of evolving primary adrenal insufficiency, measurement of plasma renin and aldosterone levels may be beneficial, as mineralocorticoid deficiency may predominate.^10,12,13

One of the most important aims of early corticosteroid supplementation is to prevent further hyponatremia by reducing a reactive increase in antidiuretic hormone secretion caused by cortisol deficiency. Corticosteroids also help to restore normal blood pressure by increasing vascular tone, as glucocorticoid receptor activation potentiates the vasoconstrictor actions of norepinephrine, angiotensin II, and other vasoconstrictors.^14,15

Which corticosteroid to use?

Which corticosteroid to use in previously undiagnosed adrenal insufficiency is controversial. The Endocrine Society¹⁰ and Japan Endocrine Society¹⁶ clinical practice guidelines recommend hydrocortisone in a 100-mg intravenous bolus followed by 200 mg over 24 hours.

The choice of hydrocortisone is justified by its superior mineralocorticoid activity.^10,16 Further, hydrocortisone is preferred over dexamethasone if the patient is known to have primary adrenal insufficiency, or if the serum potassium level is higher than 6.0 mmol/L.

Some clinicians, on the other hand, recommend dexamethasone, given as a 4-mg intravenous bolus followed by 4-mg boluses every 12 hours. Their rationale is that dexamethasone, unlike hydrocortisone, does not interfere with subsequent serum cortisol assays if the patient later undergoes ACTH stimulation testing.¹⁷ Dexamethasone may also be preferred to minimize unwanted mineralocorticoid effects, such as in neurosurgical patients at risk of brain edema.

If hydrocortisone is used, ACTH stimulation testing can be done after withholding hydrocortisone for 24 hours once the patient is stable. (It should be restarted after the test if the results are abnormal.)

Abdominal CT should be done in our patient to address the possibility of bilateral adrenal hemorrhage. However, it is preferable to wait until the patient is stabilized.

Echocardiography. Our patient is likely to have an element of cardiac failure, given her hypertension and cardiomegaly. However, decompensated heart failure is probably not the cause of her presentation. Thus, the first priority is to treat her adrenal crisis, and echocardiography should be deferred.

Increasing the norepinephrine infusion is unlikely to improve her blood pressure very much, as she is significantly volume-depleted. Further, low cortisol decreases the vascular response to norepinephrine.¹⁵

Mineralocorticoids such as fludrocortisone are used to treat primary adrenal insufficiency. However, they are not required during acute management of adrenal crisis, as 40 mg of hydrocortisone offers mineralocorticoid activity equivalent to 100 µg of fludrocortisone. Thus, the high doses of hydrocortisone used to treat adrenal crisis provide adequate mineralocorticoid therapy.^10,18

If dexamethasone is used, its effect along with normal saline supplementation would be sufficient to replete the intravenous space and bring the sodium level back up to normal in the acute setting.

CASE RESUMED: IMPROVEMENT WITH HYDROCORTISONE

The patient’s blood is drawn for serum cortisol and plasma ACTH measurements. A 100-mg intravenous bolus of hydrocortisone is given, followed by a 50-mg bolus every 6 hours until the patient stabilizes.

Twenty-four hours later, the patient states that she has more energy, and her appetite has improved. The norepinephrine infusion is stopped 48 hours after presentation, at which time her blood pressure is 120/70 mm Hg, heart rate 85 beats per minute and irregular, and temperature 36.7°C (98.1°F). Her current laboratory values include the following:

• Serum sodium 137 mmolL
• Serum potassium 4.3 mmol/L
• Hemoglobin 9.3 g/dL
• Serum cortisol (random) 7.2 μg/dL
• Plasma ACTH 752 pg/mL (10–60 pg/mL).

ESTABLISHING THE DIAGNOSIS OF ADRENAL INSUFFICIENCY

3. Which of the following is the most appropriate test to establish the diagnosis of adrenal insufficiency?

• 7 am total serum cortisol measurement
• Random serum cortisol measurement
• 7 am salivary cortisol measurement
• 24-hour urinary free cortisol measurement
• ACTH stimulation test for cortisol
• Insulin tolerance test for cortisol

These tests also help determine the type of adrenal insufficiency (primary, secondary, or tertiary) and guide further management. Secondary adrenal insufficiency is caused by inadequate pituitary ACTH secretion and subsequent inadequate cortisol production, whereas tertiary adrenal insufficiency is caused by inadequate hypothalamic corticotropin-releasing hormone secretion and subsequent inadequate ACTH and cortisol production. The diagnosis of adrenal insufficiency relies first on demonstrating inappropriately low total serum cortisol production. Subsequently, serum ACTH helps to differentiate between primary (high ACTH) and secondary or tertiary (low or inappropriately normal ACTH) adrenal insufficiency.

Each test listed above may demonstrate a low cortisol level. However, in a nonacute setting, safety concerns (especially regarding insulin tolerance testing), poor diagnostic value, feasibility (ie, the difficulty of 24-hour tests), and poor sensitivity of 7 am cortisol make the ACTH stimulation test the most appropriate test in clinical practice to establish the diagnosis of adrenal insufficiency.

7 am serum cortisol measurement

Measuring the serum cortisol level early in the morning in the nonacute setting could be of diagnostic value, as an extremely low value (< 3–5 μg/dL) is almost 100% specific for adrenal insufficiency in the absence of concurrent exogenous steroid intake. However, the very low cutoff for this test causes poor sensitivity (about 33%), as many patients have partial adrenal insufficiency and hence have higher serum cortisol levels that may even be in the normal physiologic range.^19–22

Random serum cortisol measurements

Random serum cortisol measurements are not very useful in a nonacute setting, since cortisol levels are affected by factors such as stress and hydration status. Moreover, they fluctuate during the day in a circadian rhythm.

On the other hand, random serum cortisol is a very good test to evaluate for adrenal insufficiency in the acute setting. A random value higher than 15 to 18 μg/dL is almost always associated with adequate adrenal function and generally rules out adrenal insufficiency.^11,23,24

The same principle applies to early morning salivary cortisol. Only extremely low values (< 2.65 ng/mL) may distinguish patients with adrenal insufficiency from healthy individuals, with 97.1% sensitivity and 93.3% specificity.²⁵

Of note, early morning salivary cortisol is not routinely measured in most clinical practices for evaluation of adrenal function. Hence, morning serum and morning salivary cortisol are useful screening tools and have meaningful results when their values are in the extremes of the spectrum, but they are not reliable as a single test, as they may overlook patients with partial adrenal insufficiency.

Urinary cortisol measurement

Urinary cortisol measurement is not used to diagnose adrenal insufficiency, as values can be normal in patients with partial adrenal insufficiency.

The ACTH stimulation test

The ACTH stimulation test involves an intramuscular or intravenous injection of cosyntropin (a synthetic analogue of ACTH fragment 1–24 that has the full activity of native ACTH) and measuring total serum cortisol at baseline, 30 minutes, and 60 minutes to assess the response of the adrenal glands.

The test can be done using a high or low dose of cosyntropin. The Endocrine Society’s 2016 guidelines recommend the high dose (250 μg) for most patients.¹⁰ The standard high-dose stimulation test can be done at any time during the day.²⁶ If the cosyntropin is injected intravenously, any value higher than 18 to 20 μg/dL indicates normal adrenal function and excludes adrenal insufficiency.^27,28 If intramuscular injection is used, any value higher than 16 to 18 μg/dL at 30 minutes post-consyntropin excludes adrenal insufficiency.²⁹

The ACTH stimulation test may not exclude acute secondary or tertiary adrenal insufficiency.

Insulin tolerance testing

Insulin tolerance testing remains the gold standard for diagnosing adrenal insufficiency and assessing the integrity of the pituitary-adrenal axis. However, given its difficulty to perform, safety concerns, and the availability of other reliable tests, its use in clinical practice is limited. It is nonetheless useful in assessing patients with recent onset of ACTH deficiency.^30,31

CASE RESUMED: PATIENT DISCHARGED, LOST TO FOLLOW-UP

Abdominal CT without contrast is done and demonstrates bilateral adrenal hemorrhage. Thus, the patient is diagnosed with primary acute adrenal insufficiency due to adrenal necrosis.

She is started on oral hydrocortisone and fludrocortisone after intravenous hydrocortisone is discontinued. She is counseled about adhering to medications, wearing a medical alert bracelet, giving herself emergency cortisol injections, taking higher doses of hydrocortisone if she is ill, and monitoring her INR. She is discharged home after her symptoms resolve.

The patient does not keep her scheduled appointment and is lost to follow-up. She returns 2 years later complaining of fatigue and feeling unwell. She admits that she stopped taking hydrocortisone 1 year ago after reading an online article about corticosteroid side effects. She has continued to take fludrocortisone.

MINERALOCORTICOID VS CORTICOSTEROID DEFICIENCY

4. Which of the following is least likely to be present in this patient at this time?

• Intravascular volume depletion
• Hyponatremia
• Skin hyperpigmentation
• Normokalemia
• Elevated serum ACTH level

Intravascular volume depletion

Intravascular volume depletion is the least likely to be present. This is because intravascular volume depletion is mainly secondary to mineralocorticoid deficiency rather than corticosteroid deficiency, which is not present in this patient, as she is compliant with her mineralocorticoid replacement therapy.^32,33 However, even with sufficient mineralocorticoid replacement, mild hypotension may be present in this patient due to corticosteroid deficiency-induced loss of vascular tone.

Hyponatremia

Hyponatremia in adrenal insufficiency is not due only to mineralocorticoid deficiency. Patients with secondary or tertiary adrenal insufficiency may also exhibit hyponatremia.³⁴ ACTH deficiency in such patients is not expected to cause mineralocorticoid deficiency, as ACTH has only a minor role in aldosterone production.

It has been proposed that hyponatremia in secondary adrenal insufficiency is due to cortisol deficiency resulting in an increase of antidiuretic hormone secretion.^35,36 The mechanisms for increased antidiuretic hormone include cortisol deficiency resulting in an increased corticotropin-releasing hormone level, which acts as an antidiuretic hormone secretagogue,^37,38 and cortisol directly suppressing antidiuretic hormone secretion.³⁹

In our patient, volume expansion and hyponatremia are expected due to increased antidiuretic hormone secretion as a result of corticosteroid insufficiency.

Hyperpigmentation of the skin is present only in long-standing primary adrenal insufficiency. This is due to chronic cortisol deficiency causing an increased secretion of pro-opiomelanocortin, a prohormone that is cleaved into ACTH, melanocyte-stimulating hormone, and other hormones. Melanocyte-stimulating hormone causes skin hyperpigmentation due to increased melanin synthesis.⁴⁰ The hyperpigmentation is seen in sun-exposed areas, pressure areas, palmar creases, nipples, and mucous membranes.

This patient has long-standing corticosteroid deficiency due to noncompliance and primary adrenal insufficiency, and as a result she is expected to have elevated serum ACTH and hyperpigmentation.

Normokalemia

Mineralocorticoid deficiency results in hyperkalemia and metabolic acidosis by impairing renal excretion of potassium and acid.⁴¹ This patient is compliant with her mineralocorticoid replacement regimen; thus, potassium levels and pH are expected to be normal.

TAKE-HOME POINTS

• Suspect adrenal crisis in any patient who presents with shock.
• Acute abdomen or unexplained fever could be among the manifestations.
• Initial management requires liberal normal saline intravenous fluid administration to replete the intravascular space.
• Draw blood samples for serum chemistry, cortisol, and ACTH, followed immediately by intravenous hydrocortisone supplementation.
• In critically ill patients, evaluate adrenal function with random serum cortisol; in a nonacute setting use the ACTH stimulation test.
• Chronic management of primary adrenal insufficiency requires corticosteroid and mineralocorticoid therapy.

A 71-year-old woman is brought to the emergency department by her neighbor after complaining of fatigue and light-headedness for the last 8 hours. The patient lives alone and was feeling well when she woke up this morning, but then began to feel nauseated and vomited twice.

The patient appears drowsy and confused and cannot provide any further history. Her medical records show that she was seen in the cardiology clinic 6 months ago but has not kept her appointments since then.

Her medical history includes atrial fibrillation, hypertension, type 2 diabetes mellitus, and osteoarthritis. Her medications are daily warfarin, atenolol, aspirin, candesartan, and metformin, and she takes acetaminophen as needed. She is neither a smoker nor a drug user, but she drinks alcohol occasionally. Her family history is significant for her mother’s death from breast cancer at age 55.

The neighbor confirms that the patient appeared well this morning and has not had any recent illnesses except for a minor cold last week that improved over 5 days with acetaminophen only.

INITIAL EVALUATION AND MANAGEMENT

Physical examination

On physical examination, her blood pressure is 80/40 mm Hg, respiratory rate 25 breaths per minute, oral temperature 38.3°C (100.9°F), and heart rate 130 beats per minute and irregular.

Her neck veins are flat, and her chest is clear to auscultation with normal heart sounds. Abdominal palpation elicits discomfort in the middle segments, voluntary withdrawal, and abdominal wall rigidity. Her skin feels dry and cool, with decreased turgor.

Initial treatment

The patient is given 1 L of 0.9% saline intravenously over the first hour and then is transferred to the intensive care unit, where a norepinephrine drip is started to treat her ongoing hypotension. Normal saline is continued at a rate of 500 mL per hour for the next 4 hours.

Cardiac monitoring and 12-lead electrocardiography show atrial fibrillation with a rapid ventricular response of 138 beats per minute, but electrical cardioversion is not done.

Initial laboratory tests

Of note, her international normalized ratio (INR) is 6.13, while the therapeutic range for a patient taking warfarin because of atrial fibrillation is 2.0 to 3.0.

Her blood pH is 7.34 (reference range 7.35–7.45), and her bicarbonate level is 18 mmol/L (22–26); a low pH and low bicarbonate together indicate metabolic acidosis. Her sodium level is 128 mmol/L (135–145), her chloride level is 100 mmol/L (97–107), and, as mentioned, her bicarbonate level is 18 mmol/L; therefore, her anion gap is 128 – (100 + 18) = 10 mmol/L, which is normal (≤ 10).¹

Her serum creatinine level is 1.3 mg/dL (0.5–1.1), and her blood urea nitrogen level is 35 mg/dL (7–20).

Her potassium level is 5.8 mmol/L, which is consistent with hyperkalemia (reference range 3.5–5.2).

DIFFERENTIAL DIAGNOSIS

1. Which of the following is the most likely cause of this patient’s symptoms?

• Adrenal crisis
• Cardiogenic shock due to decreased cardiac contractility
• Intracranial hemorrhage
• Acute abdomen due to small bowel obstruction
• Septic shock due to bacterial toxin-induced loss of vascular tone

Our patient is presenting with shock. Given our inability to obtain a meaningful history, the differential diagnosis is broad and includes all of the above.

Adrenal crisis

The sudden onset and laboratory results that include hyperkalemia, hyponatremia, and normal anion gap metabolic acidosis raise suspicion of adrenal crisis resulting in acute mineralocorticoid and glucocorticoid insufficiency.¹

The patient’s elevated serum creatinine and high blood urea nitrogen-to-creatinine ratio of 26.9 (reference range 10–20) also suggest intravascular volume contraction. Her low hemoglobin level and supratherapeutic INR, possibly due to an interaction between warfarin and acetaminophen combined with poor medical follow-up, raise suspicion of acute bilateral adrenal necrosis due to hemorrhage.

Bilateral adrenal hemorrhage is one cause of adrenal crisis resulting in bilateral adrenal necrosis. Risk factors for adrenal hemorrhage include anticoagulation therapy, underlying coagulopathy, postoperative states, and certain infections such as meningococcemia and Haemophilus influenzae infection.^2–5 Nevertheless, in most cases the INR is in the therapeutic range and the patient has no bleeding elsewhere.⁴ Other causes of adrenal necrosis include emboli, sepsis, and blunt trauma.^6,7

Other causes of adrenal crisis are listed in Table 3.

Cardiogenic shock

Intracranial hemorrhage can present with a decreased level of consciousness, but it is less likely to cause hypotension, as the cranial space is limited. If massive intracranial hemorrhage would occur, the increase in intracranial pressure would more likely cause hypertension by the Cushing reflex than hypotension.

Acute abdomen

Abdominal pain and rigidity along with fever can be presenting symptoms of both adrenal insufficiency and an acute abdomen due to intestinal obstruction.⁴ However, intestinal obstruction typically causes a high anion gap metabolic acidosis due to lactic acidosis, instead of the normal anion gap metabolic acidosis present in this patient.⁸ Moreover, her deranged electrolytes, supratherapeutic INR, and absence of previous gastroenterologic conditions make adrenal crisis a more likely diagnosis.

Septic shock

Septic shock would also cause fever and hypotension as bacterial toxins induce a pyrexic response and vasodilation. However, at such an early stage of sepsis, the patient would be expected to be warm and hyperemic, whereas this patient’s skin is cool and dry due to volume depletion secondary to adrenal insufficiency.⁹ Sepsis would also cause a high anion gap metabolic acidosis due to lactic acidosis, as opposed to this patient’s normal anion gap metabolic acidosis. These findings, along with the metabolic derangements and the absence of a focus of infection, make sepsis a less likely possibility.

CASE CONTINUED: CARDIOMEGALY, PERSISTENT HYPOTENSION

Blood is drawn for cultures and measurement of troponins and lactic acid, and urine samples are taken for culture and biochemical analysis. Chest radiography shows mild cardiomegaly. The patient is started empirically on vancomycin and cefepime, and her warfarin is discontinued.

Five hours after presenting to the emergency department, her blood pressure remains at 80/40 mm Hg even after receiving 3 L of normal saline intravenously.

PROMPT MANAGEMENT OF ADRENAL CRISIS

2. Which of the following is the most appropriate next step in managing this patient?

• Draw samples for serum cortisol and plasma adrenocorticotropic hormone (ACTH) levels, then give hydrocortisone 100 mg intravenously
• Perform abdominal computed tomography (CT) without contrast
• Perform transthoracic echocardiography
• Increase the norepinephrine infusion
• Immediately give fludrocortisone

First give fluids

The first step in managing a patient with suspected adrenal crisis is liberal intravenous fluid administration to replenish the depleted intravascular space. The amount and choice of fluid is empiric, but a recommendation is 1 L of normal saline or dextrose 5% in normal saline, infused quickly over the first hour and then titrated according to the patient’s fluid status.¹⁰

Measure cortisol and ACTH; start corticosteroids immediately

Immediate therapy with an appropriate stress dose of intravenous corticosteroids (eg, hydrocortisone 100 mg) is essential. However, this should be done after drawing blood for cortisol and ACTH measurements.¹⁰

Do not delay corticosteroid therapy while awaiting the results of the diagnostic tests.

In addition, in the early phase of evolving primary adrenal insufficiency, measurement of plasma renin and aldosterone levels may be beneficial, as mineralocorticoid deficiency may predominate.^10,12,13

One of the most important aims of early corticosteroid supplementation is to prevent further hyponatremia by reducing a reactive increase in antidiuretic hormone secretion caused by cortisol deficiency. Corticosteroids also help to restore normal blood pressure by increasing vascular tone, as glucocorticoid receptor activation potentiates the vasoconstrictor actions of norepinephrine, angiotensin II, and other vasoconstrictors.^14,15

Which corticosteroid to use?

Which corticosteroid to use in previously undiagnosed adrenal insufficiency is controversial. The Endocrine Society¹⁰ and Japan Endocrine Society¹⁶ clinical practice guidelines recommend hydrocortisone in a 100-mg intravenous bolus followed by 200 mg over 24 hours.

The choice of hydrocortisone is justified by its superior mineralocorticoid activity.^10,16 Further, hydrocortisone is preferred over dexamethasone if the patient is known to have primary adrenal insufficiency, or if the serum potassium level is higher than 6.0 mmol/L.

Some clinicians, on the other hand, recommend dexamethasone, given as a 4-mg intravenous bolus followed by 4-mg boluses every 12 hours. Their rationale is that dexamethasone, unlike hydrocortisone, does not interfere with subsequent serum cortisol assays if the patient later undergoes ACTH stimulation testing.¹⁷ Dexamethasone may also be preferred to minimize unwanted mineralocorticoid effects, such as in neurosurgical patients at risk of brain edema.

If hydrocortisone is used, ACTH stimulation testing can be done after withholding hydrocortisone for 24 hours once the patient is stable. (It should be restarted after the test if the results are abnormal.)

Abdominal CT should be done in our patient to address the possibility of bilateral adrenal hemorrhage. However, it is preferable to wait until the patient is stabilized.

Echocardiography. Our patient is likely to have an element of cardiac failure, given her hypertension and cardiomegaly. However, decompensated heart failure is probably not the cause of her presentation. Thus, the first priority is to treat her adrenal crisis, and echocardiography should be deferred.

Increasing the norepinephrine infusion is unlikely to improve her blood pressure very much, as she is significantly volume-depleted. Further, low cortisol decreases the vascular response to norepinephrine.¹⁵

Mineralocorticoids such as fludrocortisone are used to treat primary adrenal insufficiency. However, they are not required during acute management of adrenal crisis, as 40 mg of hydrocortisone offers mineralocorticoid activity equivalent to 100 µg of fludrocortisone. Thus, the high doses of hydrocortisone used to treat adrenal crisis provide adequate mineralocorticoid therapy.^10,18

If dexamethasone is used, its effect along with normal saline supplementation would be sufficient to replete the intravenous space and bring the sodium level back up to normal in the acute setting.

CASE RESUMED: IMPROVEMENT WITH HYDROCORTISONE

The patient’s blood is drawn for serum cortisol and plasma ACTH measurements. A 100-mg intravenous bolus of hydrocortisone is given, followed by a 50-mg bolus every 6 hours until the patient stabilizes.

Twenty-four hours later, the patient states that she has more energy, and her appetite has improved. The norepinephrine infusion is stopped 48 hours after presentation, at which time her blood pressure is 120/70 mm Hg, heart rate 85 beats per minute and irregular, and temperature 36.7°C (98.1°F). Her current laboratory values include the following:

• Serum sodium 137 mmolL
• Serum potassium 4.3 mmol/L
• Hemoglobin 9.3 g/dL
• Serum cortisol (random) 7.2 μg/dL
• Plasma ACTH 752 pg/mL (10–60 pg/mL).

ESTABLISHING THE DIAGNOSIS OF ADRENAL INSUFFICIENCY

3. Which of the following is the most appropriate test to establish the diagnosis of adrenal insufficiency?

• 7 am total serum cortisol measurement
• Random serum cortisol measurement
• 7 am salivary cortisol measurement
• 24-hour urinary free cortisol measurement
• ACTH stimulation test for cortisol
• Insulin tolerance test for cortisol

These tests also help determine the type of adrenal insufficiency (primary, secondary, or tertiary) and guide further management. Secondary adrenal insufficiency is caused by inadequate pituitary ACTH secretion and subsequent inadequate cortisol production, whereas tertiary adrenal insufficiency is caused by inadequate hypothalamic corticotropin-releasing hormone secretion and subsequent inadequate ACTH and cortisol production. The diagnosis of adrenal insufficiency relies first on demonstrating inappropriately low total serum cortisol production. Subsequently, serum ACTH helps to differentiate between primary (high ACTH) and secondary or tertiary (low or inappropriately normal ACTH) adrenal insufficiency.

Each test listed above may demonstrate a low cortisol level. However, in a nonacute setting, safety concerns (especially regarding insulin tolerance testing), poor diagnostic value, feasibility (ie, the difficulty of 24-hour tests), and poor sensitivity of 7 am cortisol make the ACTH stimulation test the most appropriate test in clinical practice to establish the diagnosis of adrenal insufficiency.

7 am serum cortisol measurement

Measuring the serum cortisol level early in the morning in the nonacute setting could be of diagnostic value, as an extremely low value (< 3–5 μg/dL) is almost 100% specific for adrenal insufficiency in the absence of concurrent exogenous steroid intake. However, the very low cutoff for this test causes poor sensitivity (about 33%), as many patients have partial adrenal insufficiency and hence have higher serum cortisol levels that may even be in the normal physiologic range.^19–22

Random serum cortisol measurements

Random serum cortisol measurements are not very useful in a nonacute setting, since cortisol levels are affected by factors such as stress and hydration status. Moreover, they fluctuate during the day in a circadian rhythm.

On the other hand, random serum cortisol is a very good test to evaluate for adrenal insufficiency in the acute setting. A random value higher than 15 to 18 μg/dL is almost always associated with adequate adrenal function and generally rules out adrenal insufficiency.^11,23,24

The same principle applies to early morning salivary cortisol. Only extremely low values (< 2.65 ng/mL) may distinguish patients with adrenal insufficiency from healthy individuals, with 97.1% sensitivity and 93.3% specificity.²⁵

Of note, early morning salivary cortisol is not routinely measured in most clinical practices for evaluation of adrenal function. Hence, morning serum and morning salivary cortisol are useful screening tools and have meaningful results when their values are in the extremes of the spectrum, but they are not reliable as a single test, as they may overlook patients with partial adrenal insufficiency.

Urinary cortisol measurement

Urinary cortisol measurement is not used to diagnose adrenal insufficiency, as values can be normal in patients with partial adrenal insufficiency.

The ACTH stimulation test

The ACTH stimulation test involves an intramuscular or intravenous injection of cosyntropin (a synthetic analogue of ACTH fragment 1–24 that has the full activity of native ACTH) and measuring total serum cortisol at baseline, 30 minutes, and 60 minutes to assess the response of the adrenal glands.

The test can be done using a high or low dose of cosyntropin. The Endocrine Society’s 2016 guidelines recommend the high dose (250 μg) for most patients.¹⁰ The standard high-dose stimulation test can be done at any time during the day.²⁶ If the cosyntropin is injected intravenously, any value higher than 18 to 20 μg/dL indicates normal adrenal function and excludes adrenal insufficiency.^27,28 If intramuscular injection is used, any value higher than 16 to 18 μg/dL at 30 minutes post-consyntropin excludes adrenal insufficiency.²⁹

The ACTH stimulation test may not exclude acute secondary or tertiary adrenal insufficiency.

Insulin tolerance testing

Insulin tolerance testing remains the gold standard for diagnosing adrenal insufficiency and assessing the integrity of the pituitary-adrenal axis. However, given its difficulty to perform, safety concerns, and the availability of other reliable tests, its use in clinical practice is limited. It is nonetheless useful in assessing patients with recent onset of ACTH deficiency.^30,31

CASE RESUMED: PATIENT DISCHARGED, LOST TO FOLLOW-UP

Abdominal CT without contrast is done and demonstrates bilateral adrenal hemorrhage. Thus, the patient is diagnosed with primary acute adrenal insufficiency due to adrenal necrosis.

She is started on oral hydrocortisone and fludrocortisone after intravenous hydrocortisone is discontinued. She is counseled about adhering to medications, wearing a medical alert bracelet, giving herself emergency cortisol injections, taking higher doses of hydrocortisone if she is ill, and monitoring her INR. She is discharged home after her symptoms resolve.

The patient does not keep her scheduled appointment and is lost to follow-up. She returns 2 years later complaining of fatigue and feeling unwell. She admits that she stopped taking hydrocortisone 1 year ago after reading an online article about corticosteroid side effects. She has continued to take fludrocortisone.

MINERALOCORTICOID VS CORTICOSTEROID DEFICIENCY

4. Which of the following is least likely to be present in this patient at this time?

• Intravascular volume depletion
• Hyponatremia
• Skin hyperpigmentation
• Normokalemia
• Elevated serum ACTH level

Intravascular volume depletion

Intravascular volume depletion is the least likely to be present. This is because intravascular volume depletion is mainly secondary to mineralocorticoid deficiency rather than corticosteroid deficiency, which is not present in this patient, as she is compliant with her mineralocorticoid replacement therapy.^32,33 However, even with sufficient mineralocorticoid replacement, mild hypotension may be present in this patient due to corticosteroid deficiency-induced loss of vascular tone.

Hyponatremia

Hyponatremia in adrenal insufficiency is not due only to mineralocorticoid deficiency. Patients with secondary or tertiary adrenal insufficiency may also exhibit hyponatremia.³⁴ ACTH deficiency in such patients is not expected to cause mineralocorticoid deficiency, as ACTH has only a minor role in aldosterone production.

It has been proposed that hyponatremia in secondary adrenal insufficiency is due to cortisol deficiency resulting in an increase of antidiuretic hormone secretion.^35,36 The mechanisms for increased antidiuretic hormone include cortisol deficiency resulting in an increased corticotropin-releasing hormone level, which acts as an antidiuretic hormone secretagogue,^37,38 and cortisol directly suppressing antidiuretic hormone secretion.³⁹

In our patient, volume expansion and hyponatremia are expected due to increased antidiuretic hormone secretion as a result of corticosteroid insufficiency.

Hyperpigmentation of the skin is present only in long-standing primary adrenal insufficiency. This is due to chronic cortisol deficiency causing an increased secretion of pro-opiomelanocortin, a prohormone that is cleaved into ACTH, melanocyte-stimulating hormone, and other hormones. Melanocyte-stimulating hormone causes skin hyperpigmentation due to increased melanin synthesis.⁴⁰ The hyperpigmentation is seen in sun-exposed areas, pressure areas, palmar creases, nipples, and mucous membranes.

This patient has long-standing corticosteroid deficiency due to noncompliance and primary adrenal insufficiency, and as a result she is expected to have elevated serum ACTH and hyperpigmentation.

Normokalemia

Mineralocorticoid deficiency results in hyperkalemia and metabolic acidosis by impairing renal excretion of potassium and acid.⁴¹ This patient is compliant with her mineralocorticoid replacement regimen; thus, potassium levels and pH are expected to be normal.

TAKE-HOME POINTS

• Suspect adrenal crisis in any patient who presents with shock.
• Acute abdomen or unexplained fever could be among the manifestations.
• Initial management requires liberal normal saline intravenous fluid administration to replete the intravascular space.
• Draw blood samples for serum chemistry, cortisol, and ACTH, followed immediately by intravenous hydrocortisone supplementation.
• In critically ill patients, evaluate adrenal function with random serum cortisol; in a nonacute setting use the ACTH stimulation test.
• Chronic management of primary adrenal insufficiency requires corticosteroid and mineralocorticoid therapy.

To the Editor: We read with great interest the article by Munyon et al¹ addressing recent developments in perioperative medicine. We would like to comment on the perioperative interruption of dual antiplatelet therapy, a common clinical problem.

Several registry analyses have shown that, with second-generation drug-eluting stents, interruption of 1 antiplatelet agent after the first month is safe.^2,3 These registries included a substantial proportion of patients whose index stenting procedure was performed for acute coronary syndrome (up to 60%).² On average, antiplatelet therapy interruption was brief (about 6 to 7 days).

Additional registry analyses have shown that surgery may be safely performed beyond the first month after drug-eluting stent placement.^4,5 Specifically, a large Danish analysis of patients with a drug-eluting stent who underwent noncardiac surgery, matched to control patients without ischemic heart disease, showed that the risk of perioperative myocardial infarction and death was not increased beyond the first month after drug-eluting stent implantation. Specifically, the risk was not increased at the 1- to 2-month and 2- to 12-month postimplantation intervals. Acute coronary syndrome was the indication for stenting in 56% of the patients.

Therefore, while surgery is preferably delayed 6 months after drug-eluting stent implantation (class I recommendation in the European Society of Cardiology guidelines), surgery may be selectively performed 1 to 6 months after drug-eluting stent implantation with an acceptable risk. This is particularly so if the index stenting was performed in the setting of stable coronary arterial disease (class IIa recommendation if stenting was performed in the setting of stable coronary arterial disease without complex procedural features; class IIb recommendation if stenting was performed in the setting of acute coronary syndrome or complex procedural features).⁶ After drug-eluting stent implantation, the earliest cutpoint for considering surgery is 1 month rather than 3 months.

When surgery is performed within this 1- to 6-month interval, thienopyridine interruption should be kept brief and dual antiplatelet therapy reinitiated as soon as possible postoperatively. In fact, when thienopyridine therapy is interrupted 1 to 6 months after drug-eluting stent implantation, stent thrombosis typically occurs more than 6 or 7 days after interruption.⁷

To the Editor: We read with great interest the article by Munyon et al¹ addressing recent developments in perioperative medicine. We would like to comment on the perioperative interruption of dual antiplatelet therapy, a common clinical problem.

Several registry analyses have shown that, with second-generation drug-eluting stents, interruption of 1 antiplatelet agent after the first month is safe.^2,3 These registries included a substantial proportion of patients whose index stenting procedure was performed for acute coronary syndrome (up to 60%).² On average, antiplatelet therapy interruption was brief (about 6 to 7 days).

Additional registry analyses have shown that surgery may be safely performed beyond the first month after drug-eluting stent placement.^4,5 Specifically, a large Danish analysis of patients with a drug-eluting stent who underwent noncardiac surgery, matched to control patients without ischemic heart disease, showed that the risk of perioperative myocardial infarction and death was not increased beyond the first month after drug-eluting stent implantation. Specifically, the risk was not increased at the 1- to 2-month and 2- to 12-month postimplantation intervals. Acute coronary syndrome was the indication for stenting in 56% of the patients.

Therefore, while surgery is preferably delayed 6 months after drug-eluting stent implantation (class I recommendation in the European Society of Cardiology guidelines), surgery may be selectively performed 1 to 6 months after drug-eluting stent implantation with an acceptable risk. This is particularly so if the index stenting was performed in the setting of stable coronary arterial disease (class IIa recommendation if stenting was performed in the setting of stable coronary arterial disease without complex procedural features; class IIb recommendation if stenting was performed in the setting of acute coronary syndrome or complex procedural features).⁶ After drug-eluting stent implantation, the earliest cutpoint for considering surgery is 1 month rather than 3 months.

When surgery is performed within this 1- to 6-month interval, thienopyridine interruption should be kept brief and dual antiplatelet therapy reinitiated as soon as possible postoperatively. In fact, when thienopyridine therapy is interrupted 1 to 6 months after drug-eluting stent implantation, stent thrombosis typically occurs more than 6 or 7 days after interruption.⁷

To the Editor: We read with great interest the article by Munyon et al¹ addressing recent developments in perioperative medicine. We would like to comment on the perioperative interruption of dual antiplatelet therapy, a common clinical problem.

Several registry analyses have shown that, with second-generation drug-eluting stents, interruption of 1 antiplatelet agent after the first month is safe.^2,3 These registries included a substantial proportion of patients whose index stenting procedure was performed for acute coronary syndrome (up to 60%).² On average, antiplatelet therapy interruption was brief (about 6 to 7 days).

Additional registry analyses have shown that surgery may be safely performed beyond the first month after drug-eluting stent placement.^4,5 Specifically, a large Danish analysis of patients with a drug-eluting stent who underwent noncardiac surgery, matched to control patients without ischemic heart disease, showed that the risk of perioperative myocardial infarction and death was not increased beyond the first month after drug-eluting stent implantation. Specifically, the risk was not increased at the 1- to 2-month and 2- to 12-month postimplantation intervals. Acute coronary syndrome was the indication for stenting in 56% of the patients.

Therefore, while surgery is preferably delayed 6 months after drug-eluting stent implantation (class I recommendation in the European Society of Cardiology guidelines), surgery may be selectively performed 1 to 6 months after drug-eluting stent implantation with an acceptable risk. This is particularly so if the index stenting was performed in the setting of stable coronary arterial disease (class IIa recommendation if stenting was performed in the setting of stable coronary arterial disease without complex procedural features; class IIb recommendation if stenting was performed in the setting of acute coronary syndrome or complex procedural features).⁶ After drug-eluting stent implantation, the earliest cutpoint for considering surgery is 1 month rather than 3 months.

When surgery is performed within this 1- to 6-month interval, thienopyridine interruption should be kept brief and dual antiplatelet therapy reinitiated as soon as possible postoperatively. In fact, when thienopyridine therapy is interrupted 1 to 6 months after drug-eluting stent implantation, stent thrombosis typically occurs more than 6 or 7 days after interruption.⁷