Cimetidine Interaction with Carbamazepine

Excerpt

To the editor: A recent report of Desmond and colleagues (1) showed delayed clearance of diazepam due to cimetidine. Similar interactions of cimetidine have been mentioned with antipyrine, oral anticoagulants, and hexobarbital. The list of the drugs thus affected by cimetidine is probably far from complete and could include carbamazepine, as indicated by the following report.

A 89-year-old woman had been treated successfully with carbamazepine (600 mg/d) for 20 years for trigeminal neuralgia although short bouts of neuralgic pain were still experienced. Two weeks before admission, a gastric ulcer was radiologically diagnosed and treated by cimetidine (400 mg/d) without modification