Rifaximin for the Treatment of Hepatic Encephalopathy

OBJECTIVE: To review the effectiveness and safety of rifaximin for the treatment of hepatic encephalopathy. METHODS: A literature search was conducted of MEDLINE (1966-September 2007), the Cochrane Database of Systematic Reviews (1995-2007), and the Cochrane Hepato-Biliary Group Reviews (2003-2007). English-language articles identified from the data sources were evaluated. All available studies were reviewed, including placebo-controlled, treatment comparison, and open label. RESULTS: Rifaximin was effective in improving behavioral, laboratory, mental status, and intellectual abnormalities associated with hepatic encephalopathy. Some studies demonstrated superior and more rapid improvement in signs or symptoms of encephalopathy during treatment with rifaximin compared with nonabsorbable disaccharides (lactulose, lactitol). Patients treated with rifaximin also required less hospitalization, had shorter duration of hospitalization, and lower hospital charges compared with lactulose-treated patients. Adverse effects of rifaximin were mostly minor gastrointestinal complaints; however, rifaximin was better tolerated than other pharmacologic treatments. CONCLUSION: Rifaximin was at least equally effective as and in some studies superior to nonabsorbable disaccharides and antimicrobials in relieving signs or symptoms observed in patients with mild-to-moderately severe hepatic encephalopathy. Future clinical trials should focus on using standardized methods of evaluating mental status and limiting enrollment to patients with mild-to-moderate, episodic, persistent, or minimal hepatic encephalopathy. Well-designed studies are needed to fully delineate the efficacy of rifaximin and other pharmacologic treatments for patients with hepatic encephalopathy.