Öz
Therapeutic drug monitoring (TDM) plays a major role in planning and optimizing the treatment of a patient, as in the treatment of epilepsy. The monitoring of antiepileptic drugs (AEDs) in the management of epilepsy is crucial because of their complex pharmacokinetic properties, narrow therapeutic index, and wide fluctuations. In this study, we aimed to investigate the 5-year TDM results of AED, which is one of the most applied groups to our laboratory, in terms of age, gender and plasma concentrations (by therapeutic limit). We also aimed to guide clinicians who diagnose and treat epilepsy patients. This study was conducted to retrospectively analyze the TDM results of patients in Eskişehir Osmangazi University Hospital between 2013-2018. The AED levels were classified as below, within, and above the reference range. The monitored drugs were valproic acid, carbamazepine, phenytoin, phenobarbital, and levetiracetam. The percent of all drug level results analyzed for valproic acid, carbamazepine, levetiracetam and phenobarbital was within the reference range. Phenytoin showed wide fluctuation and its subtherapeutic level was notably high. In practice, TDM was found to be helpful in the of adjustment drug dosage with regard to the response of individual patients.