The importance of liver diseases in the Western industrialised societies has increased continuously over the past decades. One reason is that many liver diseases, such as hepatitis and the cholestatic liver diseases, have chronic clinical courses and lead to cirrhosis. Patients are prone to get serious physical and mental complications. An example of the latter is the so-called hepatic encephalopathy. The objective of treatment is to use all available therapeutic options to prevent or postpone the necessity of liver transplantation.