Rifaximin is widely used as an antibiotic to treat gastrointestinal bacterial infections including travelers diarrhea caused by noninvasive Escherichia coli and to reduce the risk of recurrent hepatic encephalopathy and manage irritable bowel syndrome with diarrhea (IBS-D).

Its purpose is to inhibit bacterial RNA synthesis thereby reducing or eliminating susceptible bacteria in the gastrointestinal tract while having minimal systemic absorption.

Rifaximin is a semi-synthetic rifamycin antibiotic its acts locally in the intestine because it is poorly absorbed after oral administration making it effective for treating selected gastrointestinal conditions.