Sodium valproate in the treatment of the intractable childhood epileptic.

Sixty-five children with seizure disorders, who had been treated with multiple anticonvulsants but were poorly controlled, were selected from the Montreal Children's Hospital Convulsive Disorder Clinic and Neurology Service and were treated with sodium valproate (valproate). All types of seizure disorders were included in the group. Rapid oral absorption of the drug lead to peak plasma levels in one to three hours (later peaks occurring if administered after meals). A mean plasma half-life of 12.8 hours was calculated. Correlation between oral dose and plasma levels was poor. The side effects which occurred in this study were trivial. Drug interactions occurred with phenobarbital, diphenylhydantoin and clonazepam. Sixty percent of patients had a greater than 50% reduction in seizure frequency with sodium valproate, but the best response was in generalized absence seizures. Since all types of seizures responded to some degree, a trial of sodium valproate is warranted in intractable seizure disorders of childhood regardless of classification.