Effects of anticonvulsive drugs on the activity of gammaglutamyltransferase and aminotransferases in serum.

A cross-sectional study was performed to define patients at risk of developing liver disease due to long-term treatment with anticonvulsive drugs. The activities of gamma-glutamyltransferase, aspartate aminotransferase, and alanine aminotransferase and the concentrations of primidone, phenobarbital, phenytoin, and valproic acid in serum were estimated. Epileptic children before therapy were used as controls. The results indicated enzyme induction due to phenobarbital and both enzyme induction and liver cell damage or plasma membrane leakage due to phenytoin. Gamma-glutamyltransferase may be an early indicator of liver disease due to valproic acid.