title: Effects of phenytoin on serum gamma-glutamyl transpeptidase activity.
abstract: Serum gamma-glutamyl transpeptidase (gamma-GT) activity was significantly (p less than 0.001) elevated in 85 (49.7%) out of 171 epileptics receiving anticonvulsant therapy. The effects of phenytoin, phenobarbital, carbamazepine, and valproate sodium on gamma-GT activity were analyzed statistically. Among these anticonvulsants, only phenytoin seemed to be responsible for the elevation of gamma-GT activity, since its daily dose and serum level were significantly (p less than 0.05) related to the gamma-GT value. Fifteen out of 17 epileptics with abnormal serum glutamic pyruvic and/or oxaloacetic transaminase levels also showed considerable elevations of gamma-GT values. The possible relationships between the enzyme induction of liver microsomes or chronic hepatic toxicity and the elevation of serum gamma-GT activity in epileptics under treatment are also discussed.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D004790:Enzyme Induction; D004827:Epilepsy / Q000188:drug therapy / Q000201:enzymology*; D006801:Humans; D008099:Liver / Q000201:enzymology; D008875:Middle Aged; D010672:Phenytoin / Q000009:adverse effects* / Q000097:blood; D013997:Time Factors; D005723:gamma-Glutamyltransferase / Q000097:blood*
chemical_list: D010672:Phenytoin; D005723:gamma-Glutamyltransferase