Reviews for Primary Care - Fall 2007 - (Page 19) Chronic Constipation and Functional Bowel Disorders Colonic transit time and balloon expulsion Both normal Outlet delay and/or no balloon expulsion (and if anorectal manometry abnormal) Slow colonic transit; normal balloon expulsion Slow colonic transit; no balloon expulsion (and if manometry abnormal) Normal Defecation disorder Slow transit Slow transit and defecation disorder Figure 6. Evaluation and classification of idiopathic chronic constipation. Adapted with permission from Wald A.24 placebo.38 At that time, the US Food and Drug Administration (FDA) indicated that there may be patients for whom the benefits of tegaserod treatment outweigh the risks and for whom no other treatment options were available. Thus, the FDA committed to work with Novartis to allow access to tegaserod through a special program. This treatment investigational new drug (IND) protocol permits use of tegaserod to treat IBS-C and chronic idiopathic constipation in women younger than 55 years who meet specific guidelines.39 Patients must sign consent materials to ensure they are fully informed of the potential risks and benefits of tegaserod. Under this IND protocol, patients must meet strict criteria and have no known or preexisting heart problems and be in critical need of this drug. Efficacy of Bulking Agents in Patients With Constipation or IBS-C Bulking agents available in the United States include natural fibers, semisynthetic fibers, and synthetic fibers. Bulking agents are indicated for the treatment of occasional constipation. Psyllium is the only bulking agent that has been shown in randomized controlled clinical trials to benefit patients with constipation.31 Psyllium therapy has not been shown to benefit patients with IBS-C, quite possibly because the main side effect of bulking agents can be bloating, which is often a most bothersome symptom in patients suffering from IBS.40 Efficacy of Stool Softeners in Patients With Constipation or IBS-C Stool softeners available in the United States include docusate sodium and docusate calcium. Stool softeners are indicated for the treatment of occasional constipation. Clinical trials comparing stool softeners to other therapies for chronic constipation have provided inconsistent outcomes and no information on adverse effects.31 Therefore, the general consensus among experts is that stool softeners have minimal, if any, effect on improving chronic constipation symptoms. Efficacy of Stimulant Laxatives in Patients With Constipation or IBS-C Senna or bisacodyl are the active ingredients in most stimulant laxatives available in the United States. Stimulant laxatives are indicated for the treatment of occasional constipation. Although there have been some small clinical trials with the stimulant laxatives, none has demonstrated efficacy greater than other treatments for occasional constipation.31 Some individuals can develop a psychological dependency on stimulant (and other classes) laxatives, and abuse of these agents has been reported.41 Concern about myenteric nerve damage or so-called neurogenic colon with continued use of laxative therapies is not supported convincingly by clinical research. Efficacy of Osmotic Laxatives in Patients With Constipation or IBS-C There are 4 commonly used osmotic laxatives: PEG 3350, lactulose, sorbitol, and milk of magnesia. The osmotic laxatives are also indicated for the treatment of occasional constipation. PEG 3350 and lactulose have VOL. 1 NO. 1 2007 REVIEWS FOR PRIMARY CARE 19
For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.