Does carbamazepine-epoxide conjugate with glutathione? On an existing but almost forgotten possibility.

The anticonvulsant carbamazepine is widely used to treat affective disorders and behavioural disorders in non-epileptic children. We report an elevated plasma level of carbamazepine-10,11-epoxide in a cystinuric child after daily medication with 300 mg carbamazepine while the serum level of carbamazepine was in the therapeutic range. The concentrations of carbamazepine and its epoxide derivative were determined by HPLC. The formation of a glutathione conjugate of carbamazepine-10,11-epoxide is raised as a hypothesis.