Simultaneous determination of anticonvulsant drugs by gas-liquid chromatography.

A quantitative gas-liquid chromatographic method for the determination of blood levels of ethosuximide, phenobarbitone, primidone and diphenylhydantoin is described. All four compounds are determined using 1 ml of serum. A simple, direct extraction technique is employed. Ethosuximide is analysed without derivatization. Subsequent flash alkylation with trimethylanilinium hydroxide allows the simultaneous determination of phenobarbitone, primidone, and diphenylhydantoin.