Appropriateness of serum level determinations of antiepileptic drugs.

Aim: To assess the appropriateness of the determination of the serum levels of the antiepileptic drugs (AEDs) phenytoin, valproic acid and carbamazepine in inpatients of a tertiary care institution.

Methods: We performed a retrospective analysis of 602 AED serum level determinations. Appropriateness criteria regarding indication and timing were defined a priori using existing criteria from the literature.