Gamma hydroxybutyrate in the monkey. II. Effect of chronic oral anticonvulsant drugs.

Gamma hydroxybutyrate (GHB) was administered intravenously to monkeys that had been pretreated orally for 2 weeks with various anticonvulsant drugs or with L-DOPA at different dosage levels. Continuous electroencephalographic (EEG) monitoring was performed during and after GHB administration. Bloood was assayed for GHB and for the anticonvulsant drug the animal was receiving. The EEG and behavioral changes produced by GHB were improved by ethosuximide and phenobarbital, made worse by phenytoin, and unchanged by L-DOPA.