Review: Antispasmodics and antidepressants were each effective in the irritable bowel syndrome; bulking agents were not

What is the efficacy of antispasmodic drugs, antidepressant drugs, and bulking agents for the irritable bowel syndrome (IBS)?

Included studies compared antispasmodic drugs, antidepressant drugs, or bulking agents with placebo in patients > 12 years of age who had IBS diagnosed clinically or using predefined diagnostic criteria. Studies of functional bowel disorders were included if > 75% of patients had IBS; the first period of crossover studies was included. Outcomes were improvement in abdominal pain, overall global assessment, and IBS symptom scores.

MEDLINE, EMBASE/Excerpta Medica, Cochrane Library, CINAHL, PsycINFO (all to Mar 2009), and reference lists were searched for fully published randomized controlled trials (RCTs) with extractable data. Authors were contacted if essential data were missing. 56 RCTs (n = 3725) met the selection criteria: 29 (n = 2333, mean age 26 to 61 y, 35% to 100% women) evaluated antispasmodics; 15 (n = 922, mean age 32 to 49 y, 13% to 100% women) antidepressants; and 12 (n = 621, mean age 28 to 46 y, 20% to 83% women) bulking agents. 10 RCTs had low risk for bias for randomization methods, 15 for allocation concealment, 26 for blinding, 46 for follow-up, and 52 for selective reporting.

Meta-analysis showed that antispasmodic and antidepressant drugs were each better than placebo for improving abdominal pain, symptom scores, and global assessment (Table); bulking agents and placebo did not differ for any outcome (Table).

Antispasmodic and antidepressant drugs were each more effective than placebo for the irritable bowel syndrome; bulking agents did not differ from placebo.