Rifaximin versus neomycin on hyperammoniemia in chronic portal systemic encephalopathy of cirrhotics. A double-blind, randomized trial

Preliminary data suggest that rifaximin a new non-absorbable rifamycin-derivate, has beneficial effects on chronic portal systemic encephalopathy (PSE). To compare the efficacy and safety of rifaximin vs neomycin in the treatment of the hyperammoniemic state of PSE, 30 cirrhotic patients with grade I to III of PSE were randomly allocated to one of two groups: group A (15 patients) receiving rifaximin (400 mg/8h) and group B (15 patients) neomycin (1gr/8h). The duration of treatment was 21 consecutive days. Age, sex, hepatic and renal function, level of PSE, EEG and number connection test were similar in both groups. A significant decrease in blood ammonia levels was observed at the end of the treatment period in both groups; moreover rifaximin produced an earlier reduction of blood ammonia levels. The neuropsychic syndrome related to the PSE improved in both groups without significant difference. No side effects attributable to therapy were observed in the rifaximin group. These results indicate that, rifaximin is at least as effective as neomycin in the achievement and maintenance of low blood ammonia levels in cirrhotics with chronic PSE.