The gas chromatographic determination of anticonvulsant drugs in serum.

A simple and accurate method is described for the quantitative determina­ tion of trimethadione, paramethadione, ethosuximide, metharbital, methsuximide, phensuximide, mephenytoin, ethotoin, primidone and diazepam in serum. Gas chromatography, with temperature programming, is employed and each of the drugs or any combination of them may be assayed on a single specimen during a single rapid determination on 3 percent OV-17 following chloroform extraction. Retention times relative to an internal standard (methyl myristate) are given. The recovery of the drugs is from 77 to 100 percent, the instrument response is linear for each drug, and the coefficients of variation are from 3 to 9 percent.