Has Sodium Valproate Hypnotic Effects?

Abstract
Eight fasting normal human subjects were given a single dose of sodium valproate, 400 mg, phenobarbital, 60 mg, or the 2 drugs in combination, in a double-blind placebo-controlled study. The effects were assessed behaviorally and by a standard 30 min EEG, begun 1 h after the treatments were given. The recording was rated for the amount of drowsiness and sleep, independent of which drug was given. Valproate itself probably had hypnotic action which tended to be increased by the simultaneous administration of phenobarbital.