Valproic acid loading during intensive monitoring

Of 35 patients who had generalized tonic-clonic seizures during antiepileptic drug therapy withdrawal, "loading" with valproic acid was effective in limiting these seizures in 32 patients. A loading dose of approximately 12.5 mg/kg was used. This dose resulted in valproic acid levels between 284 and 458 mumol/L (41 and 66 mg/L) 1.5 hours after "loading" in six of the eight patients in whom serum concentrations were measured.