Abstracts

RATIONALE:Tiagabine, a GABA uptake inhibitor, is an effective and well-tolerated add-on antiepileptic drug in partial epilepsy. Preclinical studies and some clinical case reports have suggested an association of tiagabine with generalized spike and wave discharges (SWDs)possibly indicative of non-convulsive status epilepticus (NCSE). We evaluated the EEG effects of tiagabine as initial treatment for adult-onset partial epilepsy. Controlled monitoring of EEG chages is an essential supplement to the collection of subjective reports of CNS-related adverse effects of new antiepileptic drugs. METHODS: Altogether 39 consecutive adult patients with newly diagnosed partial seizures with or without secondary generalization took part into the study. During a six week titration period, patients were titrated to a tiagabine continuation dose of either 5,0; 7,5 or 10,0 mg BID. During follow-up patients did exit the study if they experienced a second seizure at maximum tolerated dose, experienced status epileptus or intolerable adverse events. Serial EEG recordings were made at baseline and one to four times during follow-up period varying from 6 months to 3 years. RESULTS: Altogether 39 patients were followed up with serial EEGs for over 6 months. Mean age of the patients was 43 years (range 16-74 years) and all patients had normal general intelligence. None of the patients experienced status epilepticus or adverse events suggestive of NCSE (catatonia, stupor, confusion,encephalopathy). Altogether 33/39 patients did not have any change in their serial EEG evaluation, whereas 3/39 had mild disturbance of background activity with irregular slow wave discharges (all continued tiagabine) and 3/39 had moderate disturbance of background activity and generalized SWDs (all these three patients did have second seizure at highest allowed tiagabine dose and did discontinue tiagabine therapy due to inefficacy). CONCLUSIONS: We did not find any confusional states or nonconvulsive status epilepticus in our study population of newly diagnosed patients with partial epilepsy using tiagabine as their initial antiepileptic drug. Successful tiagabine therapy was not associated with new interictal SWDs.