A case of erythromycin-induced carbamazepine toxicity

A case of serious carbamazepine toxicity as a result of concomitant erythromycin therapy is presented. Carbamazepine competes with erythromycin for metabolism by hepatic microsomal enzymes, resulting in decreased clearance of carbamazepine. Carbamazepine drug interactions will become increasingly important to psychiatrists as this anticonvulsant becomes more widely used to treat affective disorders.