Rifaximin therapy of irritable bowel syndrome.

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder characterized by abdominal pain and altered bowel habits in the absence of specific organic pathology. Although the underlying pathogenesis of IBS is not well-understood, small intestinal bacterial overgrowth (SIBO) or other abnormalities in the gut flora is believed to contribute to the development of a subset of IBS cases. Rifaximin is a poorly absorbed antimicrobial with activity against enteric pathogens. A number of studies have shown a significant improvement in IBS symptoms with antibiotic therapy including rifaximin. In this review, we discuss the pharmacokinetics, in vitro susceptibility profile, and efficacy and safety data from clinical trials of rifaximin treatment of IBS.