Probable pseudocholinesterase induction by valproic acid, carbamazepine and phenytoin leading to increased serum aspirin-esterase activity in epileptics.

The present findings show clearly that valproic acid, carbamazepine and phenytoin are each capable of significantly raising serum aspirin-esterase activity in epileptics being treated with these drugs (between p less than 0.01 and p less than 0.05). The data suggest that these antiepileptic drugs may well act as enzymatic-inducing agents upon plasma cholinesterase (or pseudocholinesterase) in epileptic patients.