This report describes two patients who developed jaundice within two weeks of receiving an amoxycillin-clavulanate potassium combination. Causes of jaundice, other than drug administration, were excluded. The patients' jaundice and clinical symptoms did not respond to stopping the drug. Ursodeoxycholic acid (750 mg/day) led to a prompt and sustained improvement in their hyperbilirubinaemia and symptoms such as pruritus and fatigue. These cases suggest that ursodeoxycholic acid may be an effective treatment for drug-associated cholestasis.