A non-absorbable rifamycin for treatment of hepatic encephalopathy.

Ammonia (NH3) plays a role in hepatic encephalopathy (HE). Agents affecting colonic ammonia production, such as non-absorbable antibiotics, decrease plasma levels of NH3 and findings of HE. The short-term efficacy of a non-absorbable rifamycin, rifaximin, was studied in comparison with paramomycin in 20 cirrhotic patients with high levels of NH3 and impaired number connection test (NCT). Both antibiotics significantly decreased ammonia-producing colonic bacteria. Rifaximin proved to be active on both aerobic and anaerobic bacteria and is thus effective, even at the dosage used, in the treatment of HE.