PLASMA LEVEL AND EFFECT OF CARBAMAZEPINE IN GRAND MAL AND PSYCHOMOTOR EPILEPSY

Abstract

In 117 patients with grand mal and psychomotor epilepsy the effect of carbamazepine alone or in combination with phenobarbital and diphenylhydantoin was registered and correlated to the plasma level of carbamazepine. Carbamazepine was found to be an effective anticonvulsant in the treatment of grand mal epilepsy. The therapeutic level was higher than 4 mg/l. Carbamazepine given alone was rather ineffective in the treatment of psychomotor seizures. The concentration of plasma carbamazepine epoxide, one of the metabolites of carbamazepine, was increased when the patients were treated with carbamazepine, in combination with phenobarbital or diphenylhydantoin or both. This may explain the better clinical effect of this combined medication, as the epoxide has an independent antiepileptic effect. The side-effects may be partly caused by the epoxide.