Treatment for Bacterial Overgrowth in the Irritable Bowel Syndrome

In this issue, Pimentel and colleagues evaluated the efficacy of a newer broad-spectrum nonabsorbable antibiotic, rifaximin, for the irritable bowel syndrome (IBS), measuring clinical response for up to 10 weeks after treatment. They concluded that rifaximin treatment for 10 days showed greater global improvement than placebo. Demonstrating sustained benefit from a short course of an antibiotic in unselected patients with IBS is certainly novel and important. However, several methodologic concerns stand in the way of drawing firm conclusions from the study.