[Drug-induced liver diseases]

About 1000 drugs produced world-wide may lead to clinically relevant hepatotoxic reactions which are unpredictable at normal doses and occur at various frequencies. Among these are well established therapeutic drugs which have been in use for years or decades as well as newly introduced drugs, the number of which is steadily increasing. For the development of drug-induced liver disease, various pathogenetic mechanisms, many risk factors and variable latency periods are known. The histological picture may imitate practically all known non-toxic liver diseases from which toxic liver disease needs to be differentiated. Patients under drug therapy require regular medical follow-up with regard to the development of toxic liver disease since the prognosis is only good with early recognition and immediate withdrawal of the alleged drug. Specific therapeutic modalities to prevent toxic liver disease are limited to paracetamol overdosage which is treated by the application of N-acetylcysteine. For other drug-induced liver diseases characterised by a prolonged course, therapy with ursodeoxycholic acid or steroids may be helpful. When fulminant drug-induced liver failure occurs, liver transplantation is the therapy of choice with a better prognosis than a conventional therapy. Despite this therapeutic option more than 40 different drugs are known to have caused lethal forms of toxic liver disease. Physicians have therefore to be alert to early recognize drug-induced liver disease and to withdraw the drug at first suspicion of the diagnosis.