Objective: To determine the efficacy, tolerability and safety of oral rifaximin given at three dose levels in patients with cirrhosis and mild to moderate hepatic encephalopathy (HE).
Design: Prospective, double-blind, randomized, parallel-group study.
Setting: Multi-centre trial in four university teaching hospitals.
Participants: Fifty-four patients with cirrhosis and mild to moderate HE.
Intervention: Seven days treatment with rifaximin, 600, 1200 or 2400 mg/day in three divided doses.
Main outcome measure: Change in the portal-systemic encephalopathy (PSE) index between baseline and day 7, calculated on the basis of mental state, asterixis, number connection test time, EEG mean cycle frequency and blood ammonia concentrations.
Results: Treatment with rifaximin was associated with an improvement in the PSE index. There was a trend towards a greater treatment effect of rifaximin with the highest dose of 2400 mg/day. Rifaximin was well tolerated; the few treatment-related adverse events showed no consistent pattern or dose relationship.
Conclusion: Rifaximin may be useful as alternative or adjuvant therapy for grade I-III hepatic encephalopathy in patients with cirrhosis at a dose of 1200 mg/day.