Details of two patients with chronic hepatitis C infection who developed features of Parkinsonism when treated with IFN-alpha 2b and ribavirin are reported. The symptoms resolved when treatment was discontinued in one patient but not in the other. Physicians should be alert to the possibility that drug-related Parkinsonism may complicate treatment of hepatitis C infection with antiviral agents; the agent most likely responsible is IFN-alpha 2b. Prompt withdrawal of treatment is mandatory but does not always guarantee reversal of the Parkinsonian features. Eur J Gastroenterol Hepatol 22:628-631 (C) 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins.