Rifaximin: beyond the traditional antibiotic activity.

Rifaximin is a non-systemic oral antibiotic derived from rifampin and characterized by a broad spectrum of antibacterial activity against Gram-positive and -negative, aerobic and anaerobic bacteria. Rifaximin was first approved in Italy in 1987 and afterwards in many other worldwide countries for the treatment of several gastrointestinal diseases. This review updates the pharmacology and pharmacodynamics of rifaximin highlighting the different actions, beyond its antibacterial activity, such as alteration of virulence, prevention of gut mucosal adherence and bacterial translocation. Moreover, rifaximin exerts some anti-inflammatory effects with only a minimal effect on the overall composition of the gut microbiota. All these properties make rifaximin a good candidate to treat various gastrointestinal diseases.