Increased plasma t
½ of vidarabine. Decreased effect by uricosurics eg, probenecid & large doses of salicylates. Increased risk of prolonged hypoglycaemic activity w/ chlorpropamide. Increased effect of warfarin, other coumarin anticoagulants. Inhibited hepatic oxidation of phenytoin. Inhibited metabolism of theophylline. Increased frequency of skin rash w/ ampicillin or amoxicillin. Enhanced bone marrow suppression by cyclophosphamide. Increased plasma conc of cyclosporin, oxipurinol, serum urate. Doubled plasma C
max & AUC of didanosine. Increased risk of hypersensitivity w/ diuretics, ACE inhibitors. Concurrent use w/ 6-mercaptopurine or azathioprine.