Long-term use of felbamate: clinical outcomes and effect of age and concomitant antiepileptic drug use on its clearance.

Purpose: To determine the effects of long-term use of felbamate (FBM) on weight, complete blood count, liver function tests, and seizure control, and also to determine the effect of age on FBM clearance.

Methods: A computerized prospective database was used to identify all subjects who had FBM listed as one of their antiepileptic drugs (AEDs) during their most recent clinic visit. Medical records from each patient were then reviewed for inclusion criteria [treatment >2 years, FBM initiated at the study clinic, data for pre-FBM (Time-1; T1), one-year exposure to FBM (Time-2; T2), and the latest visit (Time-3; T3)].