Rationale for the use of rifaximin in inflammatory bowel diseases based on clinical trial results

The cause of inflammatory bowel disease is not completely understood. However, there is now a strong evidence that resident intestinal bacteria, which are normally considered to be commensal, can initiate the pathological inflammation in a susceptible host. Although this may be a good rationale for antibiotic use in the treatment of these diseases, previous trials with different antibiotics have given controversial results while their long-term use is accompanied by an elevated number of adverse events. Rifaximin is an oral, minimally absorbed (<1% of the ingested dose), antimicrobial agent that exerts its bactericidal activity in the intestinal lumen, and is apparently free of systemic side effects. The efficacy of a new gastroresistant formulation of rifaximin (rifaximin-extended intestinal release) in moderately active Crohn’s disease has been recently shown in a multicenter, randomized, double-blind trial. In open-label studies promising results have also been obtained in ulcerative colitis and pouchi...