ABSTRACT

The effects of the seizure type, antiepileptic drug (AED) regimen, initial age of the seizures, drug tapering duration, electroencephalography (EEG) findings and serum drug levels during the withdrawal of AED, on relapse rate were assessed.

This retrospective study included 203 registered epileptic patients, followed for at least 5 years in the neurology outpatient clinic. Patients were grouped as relapse, drug tapering and remission. Groups were compared in terms of seizure and AED types, initial age of the seizures, drug tapering duration, EEG findings and current serum AED levels.

We found that seizure type, AED regimen, and drug tapering duration did not affect the relapse rate. Initiation of the seizures at an early age favored a low rate of relapse. The patients with abnormal EEG findings had higher relapse rates than those having normal or non-specific EEG findings. As expected, serum AED levels were highest in the relapse group and lowest in the drug tapering group.

While tapering the AEDs, initial age of seizures and follow up EEGs are important guides. Furthermore, serum AED levels indicate the tapering rate. Although drug regimen, seizure types and tapering duration did not alter the relapse rates in our study, tapering duration should be as long as possible in order to avoid the relapses due to abrupt drops in serum drug levels.

Keywords: Epilepsy, Recurrence; substance withdrawal syndrome