Hepatic encephalopathy is a severe complication of liver cirrhosis and is an important therapeutic challenge, with a social and economic issue. If, now, the pathophysiology is not totally understood (main role of ammonia, but a better understanding of cerebral mechanisms), the clinical presentation is well-known. Some treatments are useful (disaccharides, treatment of the trigger) but their efficiency is limited. Nevertheless, the emergence of new treatments, such as non-absorbable antibiotics (rifaximin essentially), is an interesting therapeutic tool.