We report the cases of 3 patients in whom ajmaline-induced acute hepatitis was followed by anicteric cholestasis persisting for more than 1 year after cessation of administration of the drug. Ajmaline was given for 8-16 days before the onset of acute hepatitis. Jaundice was preceded by fever, chills and abdominal pain, and was associated with hypereosinophilia. The initial lesions included centrilobular cholestasis and portal inflammatory infiltration. Jaundice lasted for 3 weeks to 11 months. In these 3 patients liver tests were still abnormal 17-26 months after ajmaline withdrawal; histological examination, performed 9-26 months after the onset of jaundice, showed a decreased number of interlobular bile ducts, ductular proliferation, and mild portal fibrosis; circulating immune complexes were demonstrated. These observations demonstrate that prolonged cholestasis can follow ajmaline-induced acute hepatitis. Persistence of cholestasis long after the withdrawal of ajmaline suggests some form of autoimmunity.