Saliva carbamazepine and phenytoin level monitoring.

Saliva carbamazepine and phenytoin samples were used to monitor treatment in 35 children aged between 2 and 14 years during a 2-year period. All phenytoin levels and over half the carbamazepine levels that were above the therapeutic range were associated with adverse effects. Dose and carbamazepine saliva levels were significantly related but no such relationship was found for phenytoin. There was no apparent relationship between the saliva level of either drug and convulsion control.