Rifaximin for irritable bowel syndrome without constipation

January 01, 0001

Rifaximin for irritable bowel syndrome without constipation

Evidence suggests that gut flora may play an important role in the pathophysiology of the irritable bowel syndrome (IBS). These US authors evaluated rifaximin, a minimally absorbed antibiotic, as treatment for IBS in two identically designed, double-blind, placebo-controlled trials (TARGET 1 and TARGET 2). Patients who had IBS without constipation were randomly assigned to either rifaximin at a dose of 550 mg or placebo, three times daily for 2 weeks, and were followed for an additional 10 weeks. Adequate relief was defined as self-reported relief of symptoms for at least 2 of the first 4 weeks after treatment.

They found: "Significantly more patients in the rifaximin group than in the placebo group had adequate relief of global IBS symptoms during the first 4 weeks after treatment (40.8% vs. 31.2% in TARGET 1; 40.6% vs. 32.2% in TARGET 2; 40.7% vs. 31.7 in the two studies combined). Similarly, more patients in the rifaximin group than in the placebo group had adequate relief of bloating (39.5% vs. 28.7% in TARGET 1; 41.0% vs. 31.9% in TARGET 2; 40.2% vs. 30.3% in the two studies combined). In addition, significantly more patients in the rifaximin group had a response to treatment as assessed by daily ratings of IBS symptoms, bloating, abdominal pain, and stool consistency. The incidence of adverse events was similar in the two groups."

The authors concluded: "Among patients who had IBS without constipation, treatment with rifaximin for 2 weeks provided significant relief of IBS symptoms, bloating, abdominal pain, and loose or watery stools."

These results should not be generalized to patients who have IBS with constipation.

For the full abstract, click here.

N Engl J Med 364:22-32, 6 January 2011 © 2011 to the Massachusetts Medical Society
Rifaximin Therapy for Patients with Irritable Bowel Syndrome without Constipation. Mark Pimentel, Anthony Lembo, William D. Chey, et al.

Category: D. Digestive. Keywords: irritable bowel syndrome, IBS, rifazimin, diarrhea, bloating, abdominal pain, randomized controlled trial, journal watch.
Synopsis edited by Dr Linda French, Toledo, Ohio. Posted on Global Family Doctor 25 January 2011

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