Sick sinus syndrome aggravated by carbamazepine therapy for epilepsy.

A case of sick sinus syndrome aggravated by carbamazepine prescribed for epilepsy is described. A 70 year old woman with previously stable psychomotor epilepsy experienced syncope of increased frequency after her anticonvulsant was changed to carbamazepine. ECG monitoring confirmed a severe sick sinus syndrome which improved on carbamazepine withdrawal. Failure to distinguish carbamazepine-induced cardiac syncope from epileptic attacks may lead to an increase in dosage and aggravation of syncope.