CONVERSION TO VALPROATE MONOTHERAPY IN NONRETARDED ADULTS WITH PRIMARY GENERALIZED TONIC CLONIC SEIZURES

Studies have demonstrated improved seizure control with fewer side effects when multidrug regimens are converted to valproate monotherapy. We studied 71 nonretarded adults, a group often unwilling to risk changes, with primary generalized tonic-clonic seizures. Their antiepileptic treatment was changed from treatment with one or more antiepileptic medicines to valproate monotherapy because of uncontrolled seizures or unacceptable side effects of the original regimen; 77% were successfully converted. Of those, 71 % became seizure-free or had a > 50% reduction in seizure frequency. The most frequent side effects of valproate were tremor, weight gain, and initial gastrointestinal irritation. Side effects were usually mild and interfered with the patient's quality of life less than those that prompted treatment conversion (sedation, gingival hypertrophy, cognitive dysfunction). One case of Reyes-like syndrome developed, but the patient recovered fully after valproate was discontinued. We concluded that conversion to valproate monotherapy is safe and effective for most treatment-resistant adults with primary generalized tonic-clonic seizures.