Serum gamma glutamyl transferase and alkaline phosphatase activities in epileptics receiving anticonvulsant therapy.

1. Serum gamma glutamyl transferase (gammaGT) and alkaline phosphatase (ALP) activities have been estimated in 49 epileptic patients taking anticonvulsant drugs. 2. Serum gammaGT activity was clearly elevated in 12 of the patients and borderline in 8, giving a 40% frequency of abnormal values. 3. Total serum ALP activity was elevated in 7 out of 33 adult patients and 2 of 16 juveniles. 4. Electrophoresis on polyacrylamide gel showed that the bone isoenzyme was responsible for most of the increased serum ALP activity and that even when the total was not elevated, the contribution of the bone isoenzyme was greater than normal. 5. There was no correlation between total serum ALP and gammaGT activities but elevations of serum gammaGT were often accompanied by an increase in the proportion of the bone enzyme in the total serum ALP activity.