Efficacy of probiotics in irritable bowel syndrome: a meta-analysis of randomized, controlled trials.

PURPOSE This study was designed to evaluate whether probiotics improve symptoms in patients with irritable bowel syndrome. METHODS PubMed, Embase, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials were searched for studies that investigated the efficacy of probiotics in the management of irritable bowel syndrome. Clinical improvement was the key outcome of interest. Data were searched within the time period of 1966 through September 2007. RESULTS Eight randomized, placebo-controlled, clinical trials met our criteria and were included in the analysis. Pooling of eight trials for the outcome of clinical improvement yielded a significant relative risk of 1.22 (95 percent confidence interval, 1.07-1.4; P = 0.0042). CONCLUSIONS Probiotics may improve symptoms of irritable bowel syndrome and can be used as supplement to standard therapy.