Scott D. Bleser, DO, FAAFP

By the time a patient sees you with a complaint of constipation, chances are she has tried a remedy or 2 and is now looking for something new. However, the abandoned remedies may yet prove useful, depending on the nature of her complaint and on her understanding of how the remedy was supposed to have worked. In this article, we discuss the benefits and limitations of several treatment options in managing a patient’s distinct condition, as assessed in part 1 (page 580).

Symptom-focused treatment

As per the ACG Task Force guidelines, initial treatment of chronic constipation (in the absence of alarm features and secondary causes) is empiric.¹ The patient’s symptoms—specifically those most bother-some—should direct your decisions. A plan so guided will also help you manage the patient’s expectations.

Address patients’ prior disappointments

Most patients will have self-treated before coming to see you, and some even will have tried prescribed regimens. Initial treatment of constipation has traditionally involved lifestyle changes (eg, diet, fluid, exercise modification), increased fiber intake, and laxatives. However, evidence supporting use of these modalities in this setting is sparse, and patient surveys often show dissatisfaction with these approaches. For instance, a web-based survey showed that 96% of patients with chronic constipation have tried some form of traditional medication (eg, bulking agents, stool softeners, laxatives).² Overall, 47% were not satisfied with their current treatment, primarily because of inadequate symptom relief and unwanted side effects.

Furthermore, patient compliance with some therapies is poor because of side effects such as flatulence, distension, and bloating. Two recently published systematic reviews evaluating treatment options for patients with chronic constipation came to similar conclusions.^1,3

Below we discuss the ACG Chronic Constipation Task Force conclusions and recommendations.¹ Explicit communication with patients about what they can expect will help ensure treatment success.

Prescribe fiber, increase water intake

Just a few clinical trials have evaluated the effects of lifestyle changes on constipation symptoms, and they have generally been poorly designed or involved small numbers of patients (TABLE).^4-7

Educating patients about proper nutrition and designating a time for daily defecation are common initial approaches, but efficacy of these strategies in this patient population has not been established (SOR: C).^4,5

Exercise has dubious value. Exercise is often recommended as a way to treat constipation because of its purported effect on reducing gastrointestinal (GI) transit time (SOR: C).⁶ However, uncontrolled studies have found that aerobic exercise does not necessarily decrease transit time and may actually prolong it.⁶

Increasing water alone generally unhelpful… Few data support the benefits of increased fluid consumption, except for dehydrated patients. In one study, increased intake (to 1 L/d) of water or isotonic fluid had no effect on the stool weight of healthy volunteers.⁴

…but fiber plus water works. However, in a study involving patients with chronic constipation, a high-fiber diet and 2 L/d of water increased frequency of bowel movements and reduced use of laxatives compared with the same diet and ad libitum fluid intake (P<.001). By binding water, fiber increases stool weight, softens stool, decreases colonic transit time, and increases GI motility.^4,5,8,9

You can recommend that patients gradually increase fiber intake over several weeks to a total of 20 g/d to 25 g/d)¹⁸ through fiber-rich foods (vegetables [eg, carrots, broccoli, string beans], fruits [eg, peaches, apples, oranges], whole-grain breads, pasta, cereal, etc) (SOR: C) or bulk supplements (eg, psyllium, methylcellulose, and polycarbophil) (SOR: B). In conjunction with other lifestyle modifications, this is a reasonable management decision.¹¹ Because failure to balance the ratio between fiber and fluid can worsen constipation, and even cause intestinal obstruction, tell patients who increase their fiber consumption to also increase their fluid intake (30 mL/kg body weight daily).^5,12

Caveats. Few data support the benefits of this approach. Epidemiologic studies show a low prevalence of constipation in countries in which fiber-rich diets are the norm,⁸ but extrapolating data from healthy populations to constipated patients may not be justified.¹³ In fact, few data from controlled trials support the use of fiber therapy in patients with constipation. In the uncontrolled Nurses’ Health Study, subjects in the highest quintile of dietary fiber intake (median intake, 20 g/d) were less likely to have constipation than those in the lowest quintile (median intake, 7 g/d).¹⁴ This general dearth of evidence led the ACG Chronic Constipation Task Force to conclude that psyllium increases stool frequency in patients with chronic constipation (ACG grade: B) but that there are insufficient data to make a recommendation about the efficacy of calcium polycarbophil, methylcellulose, and bran in this patient population (ACG grade: B).¹

Important points for patients. Counsel patients for whom you recommend fiber intake that it may take several weeks for them to experience relief,^5,8 and that long-term fiber use may cause abdominal distension, bloating, and flatulence.^4,5,8,15 Few serious adverse effects (eg, delayed gastric emptying, anorexia, and iron and calcium malabsorption) are associated with bulking agents; however, fecal impaction may occur in patients with severe colonic inertia.¹⁶

Hypersensitivity reactions have been reported in patients who ingest psyllium and in healthcare workers exposed to it.¹⁶

Osmotic laxatives may help

When increased fiber intake fails to alleviate symptoms of constipation, patients are often prescribed an osmotic laxative (eg, magnesium hydroxide, magnesium citrate, sodium phosphate, or polyethylene glycol [PEG]) (SOR: B), which promotes water secretion in the intestines.^4,8,15 However, several days may pass before the laxatives take effect, and they are indicated only for short-term use in patients with occasional constipation.¹

Common adverse effects include abdominal cramping, bloating, and flatulence.^4,10,17 More serious adverse effects include hypermagnesemia, hyperphosphatemia, hypercalcemia, hyponatremia, hypokalemia, hypovolemia, and diarrhea^1,16 ; the incidences of these events were not reported.

The ACG Task Force gave PEG and lactulose grade A recommendations, based on the quality of evidence supporting their effectiveness at improving stool frequency and stool consistency in patients with chronic constipation.¹ PEG was the only laxative shown in clinical trials to improve bowel movement frequency, stool consistency, and colonic transit time. However, this conclusion was based on analysis of all formulations—PMF-100, PEG 3350, PEG/electrolyte solutions, and high-molecular-weight PEG (PEG 4000); PEG 3350 (Miralax), the only PEG formulation approved by the FDA for use in patients with constipation, is indicated specifically for patients with occasional constipation. The Task Force determined that data were insufficient to make a recommendation for milk of magnesia (ACG grade: B).¹

Stimulant laxatives, if all else fails

Stimulants (eg, bisacodyl, cascara, senna, ricinoleic acid) cause rhythmic muscle contractions in the intestines and increase intestinal motility and secretions.^4,5,9,15,17 Controlled study data for stimulant laxatives are sparse (SOR: B).¹⁸ They work within hours,^12,15,17,19 but use them judiciously.⁹

A common adverse effect is abdominal pain; more serious adverse effects include electrolyte imbalances, allergic reactions, and hepatotoxicity.^1,16,20 However, these effects appear to be no more severe or frequent than effects of other constipation treatments. Long-term use can also cause benign pigmentation changes in the colon (Pseudomelanosis coli) and can lead to reduced colonic motility (colonic inertia).^12,16

Given safety concerns with long-term use, reserve stimulant laxatives for patients who are refractory to or who cannot tolerate other agents.^5,17 You should use them only as needed and for a brief time¹² (the general guideline for most over-the-counter products is 1 week or less). The ACG Task Force concluded that data are insufficient to make recommendations for stimulant laxatives (ACG grade: B).¹

Fiber or laxatives better?

A meta-analysis of randomized clinical trials found that fiber and laxatives increased bowel movement frequency by an overall weighted mean of 1.4 (95% confidence interval, 1.1–1.8) bowel movements per week.²¹ However, evidence was insufficient to establish whether fiber was superior to laxatives or whether one laxative class was superior to another.

Another meta-analysis found that, in studies lasting 4 weeks or less, fiber supplements and laxatives improved stool frequency (mean increase, 1.9 stool/week) and stool weight (mean increase, 476 g) but that these benefits were not clearly distinguishable from those of placebo (stool frequency, 1 stool; stool weight, 434 g).¹⁸

Large, well-designed, comparative trials of treatments for chronic constipation in adults are needed.²² Current literature contains few thoroughly reported studies of fiber and laxative use.¹⁸ Additionally, standardized measures to assess the adverse effects and outcomes (effects on quality of life) of specific agents have rarely been incorporated.^18,22 Given the problematic safety/tolerability profiles of some laxatives, it is unknown whether they improve quality of life of patients with constipation.¹⁸

TABLE
Treatments for chronic constipation

Novel therapies

Tegaserod

Tegaserod (Zelnorm) is FDA-approved for treatment of women with IBS whose primary bowel symptom is constipation, and for treatment of chronic idiopathic constipation in women and men aged <65.²³ The ACG Task Force determined that tegaserod increases the frequency of complete spontaneous bowel movements (CSBM), decreases straining, and improves stool consistency in patients with chronic constipation (ACG grade: A).¹ Tegaserod binds with high affinity at human 5-HT₄ receptors and augments peristalsis, increases colonic motility along the entire GI tract, and promotes intestinal secretions.^23,24 (For more information on tegaserod’s mode of activity, see www.jfponline.com.)

Adverse effects. The most noteworthy adverse effect of tegaserod was diarrhea, occurring as brief episodes that were generally mild (not requiring antidiarrheal drugs), transient (occurring early after initiation of treatment and resolving after a couple of days), and self-limiting.^25,26 Results of a single-blind, uncontrolled extension study in which 842 patients were administered tegaserod 2 mg or 6 mg for up to 13 months (total exposure was up to 16 months) were similar to those of shorter term studies, indicating that long-term treatment is safe and well-tolerated.²⁷

Important advice for patients. Although tegaserod is generally well tolerated, counsel patients regarding its potential risk. Ischemic colitis, a vascular disorder that results from reduced blood flow in the colon, appears as a precaution in the current package insert.²³ No cases of this condition were reported during clinical trials. Although reports of transient ischemic colitis were reported during postmarketing surveillance, they were not associated with long-term consequences, and they occurred at the expected rate in the general population and lower than the rate observed in IBS patients.^23,28 To date, no vascular mechanism has been found that links colonic ischemia with tegaserod use.²⁹ Nevertheless, patients for whom tegaserod is prescribed should be counseled to promptly report any symptoms consistent with this condition, including worsening abdominal pain, rectal bleeding, or bloody diarrhea.²³

Lubiprostone

Lubiprostone (Amitiza) is a chloride channel activator that increases secretion of intestinal fluid. This agent significantly increases stool frequency, improves stool form, and decreases straining,^30-32 and was recently FDA-approved for the treatment of patients with chronic idiopathic constipation.³³ To date, data from lubiprostone clinical trials have not been published in full. As more data become available, it will be interesting to evaluate where this agent fits into the growing treatment armamentarium for chronic constipation.

Drugs in the pipeline

Several additional pharmacologic classes with unique modes of action are under investigation for the treatment of chronic constipation, including opioid antagonists and neurotrophic factors.³⁴

When to use which agent

In the absence of specific guidelines dictating an order of treatment options for patients with chronic constipation, base your decision on such factors as the degree to which symptoms affect a patient’s daily life, results achieved with agents in the past, patient preference, and your clinical judgment and experience ( FIGURE ). Lifestyle modifications and traditional (primarily over-the-counter) therapies are typically the initial approaches for patients with milder symptoms. Patients experiencing moderate to severe constipation-associated symptoms, those who have experienced adverse effects, and those who have not achieved satisfactory relief of constipation should be evaluated for other treatment options, including prescription laxatives, tegaserod, and lubiprostone.

Because of the heterogeneity of this disorder, successful management is patient specific. Positive outcomes may include increased stool frequency, less straining, sense of complete evacuation, resolution of abdominal bloating, and passage of soft, formed stool. Optimally, these positive symptom outcomes will translate into better overall quality of life and the ability to return to normal work and personal activities. Importantly, education and continual open dialogue with the patient are crucial to managing expectations, both for the physician and for the patient.

FIGURE
Chronic primary constipation: Let symptom type and severity direct treatment choices 

When referral is indicated

Though most patients with chronic constipation can be treated successfully in the primary care setting,³⁵ a few may require referral to a gastroenterologist. Reasons may include the following:

• Suspicion of defecatory disorders (eg, pelvic floor dyssynergia)
• Lack of sufficient response to empiric treatment
• Worsening symptoms despite treatment
• Development of GI-associated alarm features requiring diagnostic procedures that may not be feasible to conduct in the primary care clinic setting (eg, balloon distension, anorectal manometry, defecography, colonic transit, barium enema, and colonoscopy).⁸

Ongoing communication with the consulting gastroenterologist is critical to maintaining optimal patient care. Use a referral form to clearly explain whether the patient is being referred for a procedure (eg, specific diagnostic test) or for a consultation (eg, temporary release of the patient to the gastroenterologist to further evaluate potential causes of symptoms); this will increase the likelihood that every-one’s expectations are satisfactorily met.

Acknowledgments

The author acknowledges the editorial assistance of Meera Nathan, PhD, Maribeth Bogush, PhD, and Sophia Shumyatsky, PharmD in the preparation of this manuscript.

CORRESPONDENCE
Scott D. Bleser, DO, FAAFP, Bellbrook Medical Center, Inc, 4336 State Route 725, Bellbrook, OH 45305-2742. E-mail: [email protected]

By the time a patient sees you with a complaint of constipation, chances are she has tried a remedy or 2 and is now looking for something new. However, the abandoned remedies may yet prove useful, depending on the nature of her complaint and on her understanding of how the remedy was supposed to have worked. In this article, we discuss the benefits and limitations of several treatment options in managing a patient’s distinct condition, as assessed in part 1 (page 580).

Symptom-focused treatment

As per the ACG Task Force guidelines, initial treatment of chronic constipation (in the absence of alarm features and secondary causes) is empiric.¹ The patient’s symptoms—specifically those most bother-some—should direct your decisions. A plan so guided will also help you manage the patient’s expectations.

Address patients’ prior disappointments

Most patients will have self-treated before coming to see you, and some even will have tried prescribed regimens. Initial treatment of constipation has traditionally involved lifestyle changes (eg, diet, fluid, exercise modification), increased fiber intake, and laxatives. However, evidence supporting use of these modalities in this setting is sparse, and patient surveys often show dissatisfaction with these approaches. For instance, a web-based survey showed that 96% of patients with chronic constipation have tried some form of traditional medication (eg, bulking agents, stool softeners, laxatives).² Overall, 47% were not satisfied with their current treatment, primarily because of inadequate symptom relief and unwanted side effects.

Furthermore, patient compliance with some therapies is poor because of side effects such as flatulence, distension, and bloating. Two recently published systematic reviews evaluating treatment options for patients with chronic constipation came to similar conclusions.^1,3

Below we discuss the ACG Chronic Constipation Task Force conclusions and recommendations.¹ Explicit communication with patients about what they can expect will help ensure treatment success.

Prescribe fiber, increase water intake

Just a few clinical trials have evaluated the effects of lifestyle changes on constipation symptoms, and they have generally been poorly designed or involved small numbers of patients (TABLE).^4-7

Educating patients about proper nutrition and designating a time for daily defecation are common initial approaches, but efficacy of these strategies in this patient population has not been established (SOR: C).^4,5

Exercise has dubious value. Exercise is often recommended as a way to treat constipation because of its purported effect on reducing gastrointestinal (GI) transit time (SOR: C).⁶ However, uncontrolled studies have found that aerobic exercise does not necessarily decrease transit time and may actually prolong it.⁶

Increasing water alone generally unhelpful… Few data support the benefits of increased fluid consumption, except for dehydrated patients. In one study, increased intake (to 1 L/d) of water or isotonic fluid had no effect on the stool weight of healthy volunteers.⁴

…but fiber plus water works. However, in a study involving patients with chronic constipation, a high-fiber diet and 2 L/d of water increased frequency of bowel movements and reduced use of laxatives compared with the same diet and ad libitum fluid intake (P<.001). By binding water, fiber increases stool weight, softens stool, decreases colonic transit time, and increases GI motility.^4,5,8,9

You can recommend that patients gradually increase fiber intake over several weeks to a total of 20 g/d to 25 g/d)¹⁸ through fiber-rich foods (vegetables [eg, carrots, broccoli, string beans], fruits [eg, peaches, apples, oranges], whole-grain breads, pasta, cereal, etc) (SOR: C) or bulk supplements (eg, psyllium, methylcellulose, and polycarbophil) (SOR: B). In conjunction with other lifestyle modifications, this is a reasonable management decision.¹¹ Because failure to balance the ratio between fiber and fluid can worsen constipation, and even cause intestinal obstruction, tell patients who increase their fiber consumption to also increase their fluid intake (30 mL/kg body weight daily).^5,12

Caveats. Few data support the benefits of this approach. Epidemiologic studies show a low prevalence of constipation in countries in which fiber-rich diets are the norm,⁸ but extrapolating data from healthy populations to constipated patients may not be justified.¹³ In fact, few data from controlled trials support the use of fiber therapy in patients with constipation. In the uncontrolled Nurses’ Health Study, subjects in the highest quintile of dietary fiber intake (median intake, 20 g/d) were less likely to have constipation than those in the lowest quintile (median intake, 7 g/d).¹⁴ This general dearth of evidence led the ACG Chronic Constipation Task Force to conclude that psyllium increases stool frequency in patients with chronic constipation (ACG grade: B) but that there are insufficient data to make a recommendation about the efficacy of calcium polycarbophil, methylcellulose, and bran in this patient population (ACG grade: B).¹

Important points for patients. Counsel patients for whom you recommend fiber intake that it may take several weeks for them to experience relief,^5,8 and that long-term fiber use may cause abdominal distension, bloating, and flatulence.^4,5,8,15 Few serious adverse effects (eg, delayed gastric emptying, anorexia, and iron and calcium malabsorption) are associated with bulking agents; however, fecal impaction may occur in patients with severe colonic inertia.¹⁶

Hypersensitivity reactions have been reported in patients who ingest psyllium and in healthcare workers exposed to it.¹⁶

Osmotic laxatives may help

When increased fiber intake fails to alleviate symptoms of constipation, patients are often prescribed an osmotic laxative (eg, magnesium hydroxide, magnesium citrate, sodium phosphate, or polyethylene glycol [PEG]) (SOR: B), which promotes water secretion in the intestines.^4,8,15 However, several days may pass before the laxatives take effect, and they are indicated only for short-term use in patients with occasional constipation.¹

Common adverse effects include abdominal cramping, bloating, and flatulence.^4,10,17 More serious adverse effects include hypermagnesemia, hyperphosphatemia, hypercalcemia, hyponatremia, hypokalemia, hypovolemia, and diarrhea^1,16 ; the incidences of these events were not reported.

The ACG Task Force gave PEG and lactulose grade A recommendations, based on the quality of evidence supporting their effectiveness at improving stool frequency and stool consistency in patients with chronic constipation.¹ PEG was the only laxative shown in clinical trials to improve bowel movement frequency, stool consistency, and colonic transit time. However, this conclusion was based on analysis of all formulations—PMF-100, PEG 3350, PEG/electrolyte solutions, and high-molecular-weight PEG (PEG 4000); PEG 3350 (Miralax), the only PEG formulation approved by the FDA for use in patients with constipation, is indicated specifically for patients with occasional constipation. The Task Force determined that data were insufficient to make a recommendation for milk of magnesia (ACG grade: B).¹

Stimulant laxatives, if all else fails

Stimulants (eg, bisacodyl, cascara, senna, ricinoleic acid) cause rhythmic muscle contractions in the intestines and increase intestinal motility and secretions.^4,5,9,15,17 Controlled study data for stimulant laxatives are sparse (SOR: B).¹⁸ They work within hours,^12,15,17,19 but use them judiciously.⁹

A common adverse effect is abdominal pain; more serious adverse effects include electrolyte imbalances, allergic reactions, and hepatotoxicity.^1,16,20 However, these effects appear to be no more severe or frequent than effects of other constipation treatments. Long-term use can also cause benign pigmentation changes in the colon (Pseudomelanosis coli) and can lead to reduced colonic motility (colonic inertia).^12,16

Given safety concerns with long-term use, reserve stimulant laxatives for patients who are refractory to or who cannot tolerate other agents.^5,17 You should use them only as needed and for a brief time¹² (the general guideline for most over-the-counter products is 1 week or less). The ACG Task Force concluded that data are insufficient to make recommendations for stimulant laxatives (ACG grade: B).¹

Fiber or laxatives better?

A meta-analysis of randomized clinical trials found that fiber and laxatives increased bowel movement frequency by an overall weighted mean of 1.4 (95% confidence interval, 1.1–1.8) bowel movements per week.²¹ However, evidence was insufficient to establish whether fiber was superior to laxatives or whether one laxative class was superior to another.

Another meta-analysis found that, in studies lasting 4 weeks or less, fiber supplements and laxatives improved stool frequency (mean increase, 1.9 stool/week) and stool weight (mean increase, 476 g) but that these benefits were not clearly distinguishable from those of placebo (stool frequency, 1 stool; stool weight, 434 g).¹⁸

Large, well-designed, comparative trials of treatments for chronic constipation in adults are needed.²² Current literature contains few thoroughly reported studies of fiber and laxative use.¹⁸ Additionally, standardized measures to assess the adverse effects and outcomes (effects on quality of life) of specific agents have rarely been incorporated.^18,22 Given the problematic safety/tolerability profiles of some laxatives, it is unknown whether they improve quality of life of patients with constipation.¹⁸

TABLE
Treatments for chronic constipation

Novel therapies

Tegaserod

Tegaserod (Zelnorm) is FDA-approved for treatment of women with IBS whose primary bowel symptom is constipation, and for treatment of chronic idiopathic constipation in women and men aged <65.²³ The ACG Task Force determined that tegaserod increases the frequency of complete spontaneous bowel movements (CSBM), decreases straining, and improves stool consistency in patients with chronic constipation (ACG grade: A).¹ Tegaserod binds with high affinity at human 5-HT₄ receptors and augments peristalsis, increases colonic motility along the entire GI tract, and promotes intestinal secretions.^23,24 (For more information on tegaserod’s mode of activity, see www.jfponline.com.)

Adverse effects. The most noteworthy adverse effect of tegaserod was diarrhea, occurring as brief episodes that were generally mild (not requiring antidiarrheal drugs), transient (occurring early after initiation of treatment and resolving after a couple of days), and self-limiting.^25,26 Results of a single-blind, uncontrolled extension study in which 842 patients were administered tegaserod 2 mg or 6 mg for up to 13 months (total exposure was up to 16 months) were similar to those of shorter term studies, indicating that long-term treatment is safe and well-tolerated.²⁷

Important advice for patients. Although tegaserod is generally well tolerated, counsel patients regarding its potential risk. Ischemic colitis, a vascular disorder that results from reduced blood flow in the colon, appears as a precaution in the current package insert.²³ No cases of this condition were reported during clinical trials. Although reports of transient ischemic colitis were reported during postmarketing surveillance, they were not associated with long-term consequences, and they occurred at the expected rate in the general population and lower than the rate observed in IBS patients.^23,28 To date, no vascular mechanism has been found that links colonic ischemia with tegaserod use.²⁹ Nevertheless, patients for whom tegaserod is prescribed should be counseled to promptly report any symptoms consistent with this condition, including worsening abdominal pain, rectal bleeding, or bloody diarrhea.²³

Lubiprostone

Lubiprostone (Amitiza) is a chloride channel activator that increases secretion of intestinal fluid. This agent significantly increases stool frequency, improves stool form, and decreases straining,^30-32 and was recently FDA-approved for the treatment of patients with chronic idiopathic constipation.³³ To date, data from lubiprostone clinical trials have not been published in full. As more data become available, it will be interesting to evaluate where this agent fits into the growing treatment armamentarium for chronic constipation.

Drugs in the pipeline

Several additional pharmacologic classes with unique modes of action are under investigation for the treatment of chronic constipation, including opioid antagonists and neurotrophic factors.³⁴

When to use which agent

In the absence of specific guidelines dictating an order of treatment options for patients with chronic constipation, base your decision on such factors as the degree to which symptoms affect a patient’s daily life, results achieved with agents in the past, patient preference, and your clinical judgment and experience ( FIGURE ). Lifestyle modifications and traditional (primarily over-the-counter) therapies are typically the initial approaches for patients with milder symptoms. Patients experiencing moderate to severe constipation-associated symptoms, those who have experienced adverse effects, and those who have not achieved satisfactory relief of constipation should be evaluated for other treatment options, including prescription laxatives, tegaserod, and lubiprostone.

Because of the heterogeneity of this disorder, successful management is patient specific. Positive outcomes may include increased stool frequency, less straining, sense of complete evacuation, resolution of abdominal bloating, and passage of soft, formed stool. Optimally, these positive symptom outcomes will translate into better overall quality of life and the ability to return to normal work and personal activities. Importantly, education and continual open dialogue with the patient are crucial to managing expectations, both for the physician and for the patient.

FIGURE
Chronic primary constipation: Let symptom type and severity direct treatment choices 

When referral is indicated

Though most patients with chronic constipation can be treated successfully in the primary care setting,³⁵ a few may require referral to a gastroenterologist. Reasons may include the following:

• Suspicion of defecatory disorders (eg, pelvic floor dyssynergia)
• Lack of sufficient response to empiric treatment
• Worsening symptoms despite treatment
• Development of GI-associated alarm features requiring diagnostic procedures that may not be feasible to conduct in the primary care clinic setting (eg, balloon distension, anorectal manometry, defecography, colonic transit, barium enema, and colonoscopy).⁸

Ongoing communication with the consulting gastroenterologist is critical to maintaining optimal patient care. Use a referral form to clearly explain whether the patient is being referred for a procedure (eg, specific diagnostic test) or for a consultation (eg, temporary release of the patient to the gastroenterologist to further evaluate potential causes of symptoms); this will increase the likelihood that every-one’s expectations are satisfactorily met.

Acknowledgments

The author acknowledges the editorial assistance of Meera Nathan, PhD, Maribeth Bogush, PhD, and Sophia Shumyatsky, PharmD in the preparation of this manuscript.

CORRESPONDENCE
Scott D. Bleser, DO, FAAFP, Bellbrook Medical Center, Inc, 4336 State Route 725, Bellbrook, OH 45305-2742. E-mail: [email protected]

By the time a patient sees you with a complaint of constipation, chances are she has tried a remedy or 2 and is now looking for something new. However, the abandoned remedies may yet prove useful, depending on the nature of her complaint and on her understanding of how the remedy was supposed to have worked. In this article, we discuss the benefits and limitations of several treatment options in managing a patient’s distinct condition, as assessed in part 1 (page 580).

Symptom-focused treatment

As per the ACG Task Force guidelines, initial treatment of chronic constipation (in the absence of alarm features and secondary causes) is empiric.¹ The patient’s symptoms—specifically those most bother-some—should direct your decisions. A plan so guided will also help you manage the patient’s expectations.

Address patients’ prior disappointments

Most patients will have self-treated before coming to see you, and some even will have tried prescribed regimens. Initial treatment of constipation has traditionally involved lifestyle changes (eg, diet, fluid, exercise modification), increased fiber intake, and laxatives. However, evidence supporting use of these modalities in this setting is sparse, and patient surveys often show dissatisfaction with these approaches. For instance, a web-based survey showed that 96% of patients with chronic constipation have tried some form of traditional medication (eg, bulking agents, stool softeners, laxatives).² Overall, 47% were not satisfied with their current treatment, primarily because of inadequate symptom relief and unwanted side effects.

Furthermore, patient compliance with some therapies is poor because of side effects such as flatulence, distension, and bloating. Two recently published systematic reviews evaluating treatment options for patients with chronic constipation came to similar conclusions.^1,3

Below we discuss the ACG Chronic Constipation Task Force conclusions and recommendations.¹ Explicit communication with patients about what they can expect will help ensure treatment success.

Prescribe fiber, increase water intake

Just a few clinical trials have evaluated the effects of lifestyle changes on constipation symptoms, and they have generally been poorly designed or involved small numbers of patients (TABLE).^4-7

Educating patients about proper nutrition and designating a time for daily defecation are common initial approaches, but efficacy of these strategies in this patient population has not been established (SOR: C).^4,5

Exercise has dubious value. Exercise is often recommended as a way to treat constipation because of its purported effect on reducing gastrointestinal (GI) transit time (SOR: C).⁶ However, uncontrolled studies have found that aerobic exercise does not necessarily decrease transit time and may actually prolong it.⁶

Increasing water alone generally unhelpful… Few data support the benefits of increased fluid consumption, except for dehydrated patients. In one study, increased intake (to 1 L/d) of water or isotonic fluid had no effect on the stool weight of healthy volunteers.⁴

…but fiber plus water works. However, in a study involving patients with chronic constipation, a high-fiber diet and 2 L/d of water increased frequency of bowel movements and reduced use of laxatives compared with the same diet and ad libitum fluid intake (P<.001). By binding water, fiber increases stool weight, softens stool, decreases colonic transit time, and increases GI motility.^4,5,8,9

You can recommend that patients gradually increase fiber intake over several weeks to a total of 20 g/d to 25 g/d)¹⁸ through fiber-rich foods (vegetables [eg, carrots, broccoli, string beans], fruits [eg, peaches, apples, oranges], whole-grain breads, pasta, cereal, etc) (SOR: C) or bulk supplements (eg, psyllium, methylcellulose, and polycarbophil) (SOR: B). In conjunction with other lifestyle modifications, this is a reasonable management decision.¹¹ Because failure to balance the ratio between fiber and fluid can worsen constipation, and even cause intestinal obstruction, tell patients who increase their fiber consumption to also increase their fluid intake (30 mL/kg body weight daily).^5,12

Caveats. Few data support the benefits of this approach. Epidemiologic studies show a low prevalence of constipation in countries in which fiber-rich diets are the norm,⁸ but extrapolating data from healthy populations to constipated patients may not be justified.¹³ In fact, few data from controlled trials support the use of fiber therapy in patients with constipation. In the uncontrolled Nurses’ Health Study, subjects in the highest quintile of dietary fiber intake (median intake, 20 g/d) were less likely to have constipation than those in the lowest quintile (median intake, 7 g/d).¹⁴ This general dearth of evidence led the ACG Chronic Constipation Task Force to conclude that psyllium increases stool frequency in patients with chronic constipation (ACG grade: B) but that there are insufficient data to make a recommendation about the efficacy of calcium polycarbophil, methylcellulose, and bran in this patient population (ACG grade: B).¹

Important points for patients. Counsel patients for whom you recommend fiber intake that it may take several weeks for them to experience relief,^5,8 and that long-term fiber use may cause abdominal distension, bloating, and flatulence.^4,5,8,15 Few serious adverse effects (eg, delayed gastric emptying, anorexia, and iron and calcium malabsorption) are associated with bulking agents; however, fecal impaction may occur in patients with severe colonic inertia.¹⁶

Hypersensitivity reactions have been reported in patients who ingest psyllium and in healthcare workers exposed to it.¹⁶

Osmotic laxatives may help

When increased fiber intake fails to alleviate symptoms of constipation, patients are often prescribed an osmotic laxative (eg, magnesium hydroxide, magnesium citrate, sodium phosphate, or polyethylene glycol [PEG]) (SOR: B), which promotes water secretion in the intestines.^4,8,15 However, several days may pass before the laxatives take effect, and they are indicated only for short-term use in patients with occasional constipation.¹

Common adverse effects include abdominal cramping, bloating, and flatulence.^4,10,17 More serious adverse effects include hypermagnesemia, hyperphosphatemia, hypercalcemia, hyponatremia, hypokalemia, hypovolemia, and diarrhea^1,16 ; the incidences of these events were not reported.

The ACG Task Force gave PEG and lactulose grade A recommendations, based on the quality of evidence supporting their effectiveness at improving stool frequency and stool consistency in patients with chronic constipation.¹ PEG was the only laxative shown in clinical trials to improve bowel movement frequency, stool consistency, and colonic transit time. However, this conclusion was based on analysis of all formulations—PMF-100, PEG 3350, PEG/electrolyte solutions, and high-molecular-weight PEG (PEG 4000); PEG 3350 (Miralax), the only PEG formulation approved by the FDA for use in patients with constipation, is indicated specifically for patients with occasional constipation. The Task Force determined that data were insufficient to make a recommendation for milk of magnesia (ACG grade: B).¹

Stimulant laxatives, if all else fails

Stimulants (eg, bisacodyl, cascara, senna, ricinoleic acid) cause rhythmic muscle contractions in the intestines and increase intestinal motility and secretions.^4,5,9,15,17 Controlled study data for stimulant laxatives are sparse (SOR: B).¹⁸ They work within hours,^12,15,17,19 but use them judiciously.⁹

A common adverse effect is abdominal pain; more serious adverse effects include electrolyte imbalances, allergic reactions, and hepatotoxicity.^1,16,20 However, these effects appear to be no more severe or frequent than effects of other constipation treatments. Long-term use can also cause benign pigmentation changes in the colon (Pseudomelanosis coli) and can lead to reduced colonic motility (colonic inertia).^12,16

Given safety concerns with long-term use, reserve stimulant laxatives for patients who are refractory to or who cannot tolerate other agents.^5,17 You should use them only as needed and for a brief time¹² (the general guideline for most over-the-counter products is 1 week or less). The ACG Task Force concluded that data are insufficient to make recommendations for stimulant laxatives (ACG grade: B).¹

Fiber or laxatives better?

A meta-analysis of randomized clinical trials found that fiber and laxatives increased bowel movement frequency by an overall weighted mean of 1.4 (95% confidence interval, 1.1–1.8) bowel movements per week.²¹ However, evidence was insufficient to establish whether fiber was superior to laxatives or whether one laxative class was superior to another.

Another meta-analysis found that, in studies lasting 4 weeks or less, fiber supplements and laxatives improved stool frequency (mean increase, 1.9 stool/week) and stool weight (mean increase, 476 g) but that these benefits were not clearly distinguishable from those of placebo (stool frequency, 1 stool; stool weight, 434 g).¹⁸

Large, well-designed, comparative trials of treatments for chronic constipation in adults are needed.²² Current literature contains few thoroughly reported studies of fiber and laxative use.¹⁸ Additionally, standardized measures to assess the adverse effects and outcomes (effects on quality of life) of specific agents have rarely been incorporated.^18,22 Given the problematic safety/tolerability profiles of some laxatives, it is unknown whether they improve quality of life of patients with constipation.¹⁸

TABLE
Treatments for chronic constipation

Novel therapies

Tegaserod

Tegaserod (Zelnorm) is FDA-approved for treatment of women with IBS whose primary bowel symptom is constipation, and for treatment of chronic idiopathic constipation in women and men aged <65.²³ The ACG Task Force determined that tegaserod increases the frequency of complete spontaneous bowel movements (CSBM), decreases straining, and improves stool consistency in patients with chronic constipation (ACG grade: A).¹ Tegaserod binds with high affinity at human 5-HT₄ receptors and augments peristalsis, increases colonic motility along the entire GI tract, and promotes intestinal secretions.^23,24 (For more information on tegaserod’s mode of activity, see www.jfponline.com.)

Adverse effects. The most noteworthy adverse effect of tegaserod was diarrhea, occurring as brief episodes that were generally mild (not requiring antidiarrheal drugs), transient (occurring early after initiation of treatment and resolving after a couple of days), and self-limiting.^25,26 Results of a single-blind, uncontrolled extension study in which 842 patients were administered tegaserod 2 mg or 6 mg for up to 13 months (total exposure was up to 16 months) were similar to those of shorter term studies, indicating that long-term treatment is safe and well-tolerated.²⁷

Important advice for patients. Although tegaserod is generally well tolerated, counsel patients regarding its potential risk. Ischemic colitis, a vascular disorder that results from reduced blood flow in the colon, appears as a precaution in the current package insert.²³ No cases of this condition were reported during clinical trials. Although reports of transient ischemic colitis were reported during postmarketing surveillance, they were not associated with long-term consequences, and they occurred at the expected rate in the general population and lower than the rate observed in IBS patients.^23,28 To date, no vascular mechanism has been found that links colonic ischemia with tegaserod use.²⁹ Nevertheless, patients for whom tegaserod is prescribed should be counseled to promptly report any symptoms consistent with this condition, including worsening abdominal pain, rectal bleeding, or bloody diarrhea.²³

Lubiprostone

Lubiprostone (Amitiza) is a chloride channel activator that increases secretion of intestinal fluid. This agent significantly increases stool frequency, improves stool form, and decreases straining,^30-32 and was recently FDA-approved for the treatment of patients with chronic idiopathic constipation.³³ To date, data from lubiprostone clinical trials have not been published in full. As more data become available, it will be interesting to evaluate where this agent fits into the growing treatment armamentarium for chronic constipation.

Drugs in the pipeline

Several additional pharmacologic classes with unique modes of action are under investigation for the treatment of chronic constipation, including opioid antagonists and neurotrophic factors.³⁴

When to use which agent

In the absence of specific guidelines dictating an order of treatment options for patients with chronic constipation, base your decision on such factors as the degree to which symptoms affect a patient’s daily life, results achieved with agents in the past, patient preference, and your clinical judgment and experience ( FIGURE ). Lifestyle modifications and traditional (primarily over-the-counter) therapies are typically the initial approaches for patients with milder symptoms. Patients experiencing moderate to severe constipation-associated symptoms, those who have experienced adverse effects, and those who have not achieved satisfactory relief of constipation should be evaluated for other treatment options, including prescription laxatives, tegaserod, and lubiprostone.

Because of the heterogeneity of this disorder, successful management is patient specific. Positive outcomes may include increased stool frequency, less straining, sense of complete evacuation, resolution of abdominal bloating, and passage of soft, formed stool. Optimally, these positive symptom outcomes will translate into better overall quality of life and the ability to return to normal work and personal activities. Importantly, education and continual open dialogue with the patient are crucial to managing expectations, both for the physician and for the patient.

FIGURE
Chronic primary constipation: Let symptom type and severity direct treatment choices 

When referral is indicated

Though most patients with chronic constipation can be treated successfully in the primary care setting,³⁵ a few may require referral to a gastroenterologist. Reasons may include the following:

• Suspicion of defecatory disorders (eg, pelvic floor dyssynergia)
• Lack of sufficient response to empiric treatment
• Worsening symptoms despite treatment
• Development of GI-associated alarm features requiring diagnostic procedures that may not be feasible to conduct in the primary care clinic setting (eg, balloon distension, anorectal manometry, defecography, colonic transit, barium enema, and colonoscopy).⁸

Ongoing communication with the consulting gastroenterologist is critical to maintaining optimal patient care. Use a referral form to clearly explain whether the patient is being referred for a procedure (eg, specific diagnostic test) or for a consultation (eg, temporary release of the patient to the gastroenterologist to further evaluate potential causes of symptoms); this will increase the likelihood that every-one’s expectations are satisfactorily met.

Acknowledgments

The author acknowledges the editorial assistance of Meera Nathan, PhD, Maribeth Bogush, PhD, and Sophia Shumyatsky, PharmD in the preparation of this manuscript.

CORRESPONDENCE
Scott D. Bleser, DO, FAAFP, Bellbrook Medical Center, Inc, 4336 State Route 725, Bellbrook, OH 45305-2742. E-mail: [email protected]

When a patient tells you she is constipated, what does she really mean? You would think that a report so common about a complaint so universal would be immediately clear. But, in fact, there is no standard, widely accepted definition.

Researchers define constipation by diagnostic criteria (eg, Rome II).¹

Recommendation grades based on the American College of Gastroenterology (ACG) Chronic Constipation Task Force are presented on our web site (TABLE W1),⁴ as are the strength of recommendations taxonomy (SORT) grades for evidence (TABLE W2).⁵

Methods

References were selected by searching Medline and InfoRetriever using the terms constipation or chronic constipation and socioeconomics, prevalence, impact, treatment(s), patient unmet needs, patient needs, and definition. Articles from 1994 to November 2005 were included. Searches were restricted to manuscripts written in English and to those examining constipation in adults (aged 18 and older).

The focus of this article is on the North American population. A note-worthy limitation is that, although references for prevalence and socioeconomic impact are recent, most statistics in these references are from data more than 10 years old.

Using a symptom-based evaluation

The first step in this evaluation (FIGURE) is to ask the patient to clearly describe her symptoms.

FIGURE
Symptom-based approach to evaluating constipation

Helpful aids in assessing symptoms

The Rome II criteria (TABLE 1), developed by a panel of experts, are one frame of reference in which to assess a patient’s symptoms.¹

Recently, to capture a more clinically relevant definition, the American College of Gastroenterology’s Chronic Constipation Task Force described constipation as a symptom-based disorder characterized by unsatisfactory defecation—infrequent stool or difficult stool passage, including straining, incomplete evacuation, hard/lumpy stool, increased time to passing stool, use of manual maneuvers, or sense of difficulty passing stool (TABLE 1).⁴

TABLE 1
Definitions of chronic constipation

Specifics to look for in history and physical

Get a thorough account of the patient’s medical and surgical history, the family’s history, and medications currently used for other conditions (TABLE 2).

Ask about medications or maneuvers the patient has tried as constipation remedies, and consider potential reasons for ineffectiveness of medications. For instance, patients often do not take enough of an agent or do not give it enough time to work.

In the physical examination, be sure to include a digital rectal exam (looking for presence of skin tags, hemorrhoids, masses, etc).

Are alarm features present? Symptoms that are red flags suggestive of organic disease include rectal bleeding, symptom onset in patients older than 50 years, family history of colorectal cancer or inflammatory bowel disease, and key laboratory abnormalities (eg, anemia, leukocytosis), among others (TABLE 3).⁴ Such symptoms of course necessitate directed evaluation of the potential underlying cause.

Clues to primary or secondary constipation. Findings from the physical examination and patient history may also help distinguish between constipation that is primary (no known cause) and that which is secondary to a physiologic disorder (eg, hemorrhoids, strictures, anal fissure), medication (eg, antidepressants, anti-spasmodics), or lifestyle habits (eg, inactivity, inadequate fiber and fluid intake) (TABLE 2).^6-11

When abdominal pain is the chief symptom. If the patient reports abdominal pain, explore the possibility of irritable bowel syndrome with constipation (IBS-C). Symptom overlap between IBS-C and chronic constipation is common and includes hard, lumpy stools, straining, and feelings of incomplete evacuation. Abdominal pain is the main distinguishing feature.¹

In the case of IBS, abdominal pain is the primary symptom and, by definition, is associated with a change in stool frequency or form. With chronic constipation, however, abdominal pain is not necessarily the primary symptom and is not always related to changes in bowel habits.¹

What symptom duration tells you. Symptom duration can aid in determining whether constipation is occasional or chronic, which may influence the treatment course you recommend. In the absence of clear-cut guidelines differentiating these subcategories, the distinction is often arbitrary: constipation is considered acute/occasional if it lasts less than 3 months and chronic if it lasts 3 months or more.⁴

TABLE 2
Causes of secondary constipation^6-11

TABLE 3
Select alarm features suggesting dire underlying causes^4,7

When are diagnostic tests warranted?

The choice of diagnostic tests and the timing of those tests is a judgment call in each case, ultimately based on your experience and clinical assessment. There are no universally accepted standards, but recently published evidence-based recommendations by the ACG Task Force on Chronic Constipation serve as a useful guide.

Per these recommendations, for patients with chronic constipation who do not exhibit alarm features, evidence is insufficient to recommend routine diagnostic testing (eg, colonoscopy, flexible sigmoidoscopy, barium enema, serum calcium, thyroid function tests) (ACG grade: C). In the presence of alarm features, however, relevant diagnostic tests are indicated (ACG grade: C).

Routine colon cancer screening tests for all patients aged 50 years or older is recommended (ACG grade: C).

In summary, per these guidelines, the routine initial approach to patients with chronic constipation but without alarm features is empiric treatment without diagnostic testing.⁴

Acknowledgments

The author acknowledges the editorial assistance of Meera Nathan, PhD, Maribeth Bogush, PhD, and Sophia Shumyatsky, PharmD in the preparation of this manuscript.

CORRESPONDENCE
Scott D. Bleser, DO, FAAFP, Bellbrook Medical Center, Inc, 4336 State Route 725, Bellbrook, OH 45305-2742. E-mail: [email protected]

When a patient tells you she is constipated, what does she really mean? You would think that a report so common about a complaint so universal would be immediately clear. But, in fact, there is no standard, widely accepted definition.

Researchers define constipation by diagnostic criteria (eg, Rome II).¹

Recommendation grades based on the American College of Gastroenterology (ACG) Chronic Constipation Task Force are presented on our web site (TABLE W1),⁴ as are the strength of recommendations taxonomy (SORT) grades for evidence (TABLE W2).⁵

Methods

References were selected by searching Medline and InfoRetriever using the terms constipation or chronic constipation and socioeconomics, prevalence, impact, treatment(s), patient unmet needs, patient needs, and definition. Articles from 1994 to November 2005 were included. Searches were restricted to manuscripts written in English and to those examining constipation in adults (aged 18 and older).

The focus of this article is on the North American population. A note-worthy limitation is that, although references for prevalence and socioeconomic impact are recent, most statistics in these references are from data more than 10 years old.

Using a symptom-based evaluation

The first step in this evaluation (FIGURE) is to ask the patient to clearly describe her symptoms.

FIGURE
Symptom-based approach to evaluating constipation

Helpful aids in assessing symptoms

The Rome II criteria (TABLE 1), developed by a panel of experts, are one frame of reference in which to assess a patient’s symptoms.¹

Recently, to capture a more clinically relevant definition, the American College of Gastroenterology’s Chronic Constipation Task Force described constipation as a symptom-based disorder characterized by unsatisfactory defecation—infrequent stool or difficult stool passage, including straining, incomplete evacuation, hard/lumpy stool, increased time to passing stool, use of manual maneuvers, or sense of difficulty passing stool (TABLE 1).⁴

TABLE 1
Definitions of chronic constipation

Specifics to look for in history and physical

Get a thorough account of the patient’s medical and surgical history, the family’s history, and medications currently used for other conditions (TABLE 2).

Ask about medications or maneuvers the patient has tried as constipation remedies, and consider potential reasons for ineffectiveness of medications. For instance, patients often do not take enough of an agent or do not give it enough time to work.

In the physical examination, be sure to include a digital rectal exam (looking for presence of skin tags, hemorrhoids, masses, etc).

Are alarm features present? Symptoms that are red flags suggestive of organic disease include rectal bleeding, symptom onset in patients older than 50 years, family history of colorectal cancer or inflammatory bowel disease, and key laboratory abnormalities (eg, anemia, leukocytosis), among others (TABLE 3).⁴ Such symptoms of course necessitate directed evaluation of the potential underlying cause.

Clues to primary or secondary constipation. Findings from the physical examination and patient history may also help distinguish between constipation that is primary (no known cause) and that which is secondary to a physiologic disorder (eg, hemorrhoids, strictures, anal fissure), medication (eg, antidepressants, anti-spasmodics), or lifestyle habits (eg, inactivity, inadequate fiber and fluid intake) (TABLE 2).^6-11

When abdominal pain is the chief symptom. If the patient reports abdominal pain, explore the possibility of irritable bowel syndrome with constipation (IBS-C). Symptom overlap between IBS-C and chronic constipation is common and includes hard, lumpy stools, straining, and feelings of incomplete evacuation. Abdominal pain is the main distinguishing feature.¹

In the case of IBS, abdominal pain is the primary symptom and, by definition, is associated with a change in stool frequency or form. With chronic constipation, however, abdominal pain is not necessarily the primary symptom and is not always related to changes in bowel habits.¹

What symptom duration tells you. Symptom duration can aid in determining whether constipation is occasional or chronic, which may influence the treatment course you recommend. In the absence of clear-cut guidelines differentiating these subcategories, the distinction is often arbitrary: constipation is considered acute/occasional if it lasts less than 3 months and chronic if it lasts 3 months or more.⁴

TABLE 2
Causes of secondary constipation^6-11

TABLE 3
Select alarm features suggesting dire underlying causes^4,7

When are diagnostic tests warranted?

The choice of diagnostic tests and the timing of those tests is a judgment call in each case, ultimately based on your experience and clinical assessment. There are no universally accepted standards, but recently published evidence-based recommendations by the ACG Task Force on Chronic Constipation serve as a useful guide.

Per these recommendations, for patients with chronic constipation who do not exhibit alarm features, evidence is insufficient to recommend routine diagnostic testing (eg, colonoscopy, flexible sigmoidoscopy, barium enema, serum calcium, thyroid function tests) (ACG grade: C). In the presence of alarm features, however, relevant diagnostic tests are indicated (ACG grade: C).

Routine colon cancer screening tests for all patients aged 50 years or older is recommended (ACG grade: C).

In summary, per these guidelines, the routine initial approach to patients with chronic constipation but without alarm features is empiric treatment without diagnostic testing.⁴

Acknowledgments

The author acknowledges the editorial assistance of Meera Nathan, PhD, Maribeth Bogush, PhD, and Sophia Shumyatsky, PharmD in the preparation of this manuscript.

CORRESPONDENCE
Scott D. Bleser, DO, FAAFP, Bellbrook Medical Center, Inc, 4336 State Route 725, Bellbrook, OH 45305-2742. E-mail: [email protected]

When a patient tells you she is constipated, what does she really mean? You would think that a report so common about a complaint so universal would be immediately clear. But, in fact, there is no standard, widely accepted definition.

Researchers define constipation by diagnostic criteria (eg, Rome II).¹

Recommendation grades based on the American College of Gastroenterology (ACG) Chronic Constipation Task Force are presented on our web site (TABLE W1),⁴ as are the strength of recommendations taxonomy (SORT) grades for evidence (TABLE W2).⁵

Methods

References were selected by searching Medline and InfoRetriever using the terms constipation or chronic constipation and socioeconomics, prevalence, impact, treatment(s), patient unmet needs, patient needs, and definition. Articles from 1994 to November 2005 were included. Searches were restricted to manuscripts written in English and to those examining constipation in adults (aged 18 and older).

The focus of this article is on the North American population. A note-worthy limitation is that, although references for prevalence and socioeconomic impact are recent, most statistics in these references are from data more than 10 years old.

Using a symptom-based evaluation

The first step in this evaluation (FIGURE) is to ask the patient to clearly describe her symptoms.

FIGURE
Symptom-based approach to evaluating constipation

Helpful aids in assessing symptoms

The Rome II criteria (TABLE 1), developed by a panel of experts, are one frame of reference in which to assess a patient’s symptoms.¹

Recently, to capture a more clinically relevant definition, the American College of Gastroenterology’s Chronic Constipation Task Force described constipation as a symptom-based disorder characterized by unsatisfactory defecation—infrequent stool or difficult stool passage, including straining, incomplete evacuation, hard/lumpy stool, increased time to passing stool, use of manual maneuvers, or sense of difficulty passing stool (TABLE 1).⁴

TABLE 1
Definitions of chronic constipation

Specifics to look for in history and physical

Get a thorough account of the patient’s medical and surgical history, the family’s history, and medications currently used for other conditions (TABLE 2).

Ask about medications or maneuvers the patient has tried as constipation remedies, and consider potential reasons for ineffectiveness of medications. For instance, patients often do not take enough of an agent or do not give it enough time to work.

In the physical examination, be sure to include a digital rectal exam (looking for presence of skin tags, hemorrhoids, masses, etc).

Are alarm features present? Symptoms that are red flags suggestive of organic disease include rectal bleeding, symptom onset in patients older than 50 years, family history of colorectal cancer or inflammatory bowel disease, and key laboratory abnormalities (eg, anemia, leukocytosis), among others (TABLE 3).⁴ Such symptoms of course necessitate directed evaluation of the potential underlying cause.

Clues to primary or secondary constipation. Findings from the physical examination and patient history may also help distinguish between constipation that is primary (no known cause) and that which is secondary to a physiologic disorder (eg, hemorrhoids, strictures, anal fissure), medication (eg, antidepressants, anti-spasmodics), or lifestyle habits (eg, inactivity, inadequate fiber and fluid intake) (TABLE 2).^6-11

When abdominal pain is the chief symptom. If the patient reports abdominal pain, explore the possibility of irritable bowel syndrome with constipation (IBS-C). Symptom overlap between IBS-C and chronic constipation is common and includes hard, lumpy stools, straining, and feelings of incomplete evacuation. Abdominal pain is the main distinguishing feature.¹

In the case of IBS, abdominal pain is the primary symptom and, by definition, is associated with a change in stool frequency or form. With chronic constipation, however, abdominal pain is not necessarily the primary symptom and is not always related to changes in bowel habits.¹

What symptom duration tells you. Symptom duration can aid in determining whether constipation is occasional or chronic, which may influence the treatment course you recommend. In the absence of clear-cut guidelines differentiating these subcategories, the distinction is often arbitrary: constipation is considered acute/occasional if it lasts less than 3 months and chronic if it lasts 3 months or more.⁴

TABLE 2
Causes of secondary constipation^6-11

TABLE 3
Select alarm features suggesting dire underlying causes^4,7

When are diagnostic tests warranted?

The choice of diagnostic tests and the timing of those tests is a judgment call in each case, ultimately based on your experience and clinical assessment. There are no universally accepted standards, but recently published evidence-based recommendations by the ACG Task Force on Chronic Constipation serve as a useful guide.

Per these recommendations, for patients with chronic constipation who do not exhibit alarm features, evidence is insufficient to recommend routine diagnostic testing (eg, colonoscopy, flexible sigmoidoscopy, barium enema, serum calcium, thyroid function tests) (ACG grade: C). In the presence of alarm features, however, relevant diagnostic tests are indicated (ACG grade: C).

Routine colon cancer screening tests for all patients aged 50 years or older is recommended (ACG grade: C).

In summary, per these guidelines, the routine initial approach to patients with chronic constipation but without alarm features is empiric treatment without diagnostic testing.⁴

Acknowledgments

The author acknowledges the editorial assistance of Meera Nathan, PhD, Maribeth Bogush, PhD, and Sophia Shumyatsky, PharmD in the preparation of this manuscript.

CORRESPONDENCE
Scott D. Bleser, DO, FAAFP, Bellbrook Medical Center, Inc, 4336 State Route 725, Bellbrook, OH 45305-2742. E-mail: [email protected]