How do you spell relief for irritable bowel syndrome?
Many treatment options lack strong evidence for their efficacy. Others have proven efficacy, but restricted use.
| TREATMENT | CLINICAL EFFICACY | SOR | COMMENTS |
|---|---|---|---|
| Hypnotherapy47 | Global symptom relief, improvement in individual symptom scores | B | Trials, though many, were of poor quality, but did show significant benefit. A large, randomized placebo-controlled trial is needed to demonstrate benefit |
| Psychotherapy (Cognitive behavioral therapy, biofeedback)1,48 | Global symptom relief, improvement in individual symptom scores (NNT=1–2) | B | Significant reduction in symptoms, but did not eliminate them. To maximize the likelihood of success, biofeedback techniques should be administered by a trained professional. Recommended as part of an overall treatment plan |
| SOR, strength of recommendation; NNT, number needed to treat. | |||
IBS with diarrhea
Options all have “but” clauses
Alosetron, the 5-HT3 receptor antagonist, has demonstrated efficacy in women (specifically) with IBS with diarrhea and has a grade A treatment recommendation from the American College of Gastroenterology.29,30 Given the concerns about severe constipation and ischemic colitis, alosetron was withdrawn from the market in November 2000 but was reintroduced in June 2002 under a limited-use program for patients with severe IBS with diarrhea, in whom standard therapy has failed (SOR: A). Research has since shown that IBS patients have a greater risk for ischemic colitis than the general population.49
Loperamide, a μ-opioid receptor agonist, which does not cross the blood-brain barrier, can be started at bedtime or in the morning at 2 mg and slowly titrated daily to effect. The effect, however, is limited to the bowel habits (SOR: B).38
Anticholinergics can be used for abdominal pain or discomfort, particularly in patients with IBS with diarrhea. Despite their lengthy history and broad use in IBS populations, limited evidence supports their efficacy, and many are not available in the US (SOR: B).35,36
Tricyclic antidepressants (TCAs) exert their effects by blocking the muscarinic receptors. TCAs can provide relief to patients with severe or refractory pain but perceived social stigma associated with taking antidepressants can be a barrier to this therapeutic approach (SOR: B).36,41
IBS with constipation
Laxatives, lubiprostone are options
Osmotic laxatives such as polyethylene glycol or lactulose can improve constipation. Despite widespread over-the-counter and prescription use, however, evidence is lacking for their efficacy and tolerability in IBS (SOR: B).39
Lubiprostone, a ClC2 chloride-channel opener, improved individual symptoms scores in 50 patients with IBS with constipation compared with placebo in a small phase II dose-ranging study (SOR: B).37
Tegaserod, a partial 5-HT4 receptor agonist, facilitates neurotransmission in the gut that is involved in motility and secretion and produces global symptom relief.31 The American College of Gastroenterology gave tegaserod a grade A recommendation for the treatment of women with IBS with constipation.29
On March 30, 2007, Novartis Pharmaceuticals agreed to stop selling tegaserod maleate (Zelnorm) because a safety analysis found a higher chance of heart attack, stroke, and worsening chest pain that could become a heart attack in patients treated with Zelnorm, compared with those receiving placebo.32 In July 2007, the FDA announced that it would permit restricted use of the drug in patients who meet strict criteria, have no known or pre-existing heart problems, and who are in critical need of the drug.33
Polycarbophil and ispaghula husk are the only fibers to have demonstrated any significant benefit in clinical trials for constipation,35 but may make pain and bloating worse (SOR: B).
SSRIS and low-dose benzodiazepines are an option for patients who have coexisting psychological illness.41 There is limited evidence for SSRI treatment (citalopram, paroxetine), either alone or in combination with additional treatments (SOR: B).35,41-43
IBS with mixed/unspecified bowel habit
Consider therapy
Cognitive behavioral therapy or other standard psychotherapy may be beneficial in many IBS patients (SOR: B).1,48
Peppermint oil for IBS is efficacious in recurrent abdominal pain compared with placebo and anticholinergic agents (SOR: B).39,50
Hypnosis has had a therapeutic impact on patients with IBS, even those whose conditions were refractory to other forms of therapy (SOR: B).47
Certain probiotic therapies have shown improvement in global symptoms and may prove to be promising therapeutic agents (SOR: B).46
Acupuncture has shown no proven efficacy in IBS (SOR: C).44
Some Chinese herbal medicines may improve the symptoms of IBS. Positive findings from trials should be interpreted with caution, though, due to inadequate methodology, small sample sizes, and lack of confirming data. In addition, herbal remedies may contain unknown substances that can pose serious risk for adverse events and drug interactions (SOR: C).45
Antibiotics for IBS patients with small intestinal bacterial overgrowth can provide some relief, according to Pimentel and colleagues,14 but other groups have not been able to duplicate these findings. Rifaximin in IBS and IBS-like symptoms has shown a sustained benefit (SOR: B).34
