Corticosteroid-sparing effect of rifaximin, a nonabsorbable oral antibiotic, in active ulcerative colitis: Preliminary clinical experience

The role of enteric flora in the pathogenesis of inflammatory bowel disease constitutes the rationale for the use of antibiotics as adjuvant agents in the treatment of ulcerative colitis (UC) and Crohn's disease. The aim of this study was to assess, in a preliminary fashion, the efficacy of the nonabsorbable antibiotic rifaximin in the treatment of exacerbation of UC in patients with a history of poor corticosteroid tolerance. This open label pilot study was conducted in the Gastroenterology Unit, S. Raffaele University Hospital (Milan, Italy). Male and female patients aged 18 to 65 years with an established diagnosis of left-sided UC who were experiencing a clinical relapse during maintenance treatment with mesalamine and with a history of poor tolerance to corticosteroid therapy were included in the study. They received rifaximin 400 mg BID for 4 weeks while continuing to receive mesalamine 2.4 g/d. Disease activity before and after treatment was assessed using Rachmilewitz's Activity Index (RAI). A final RAI score