[Topiramate--a new antiepileptic agents].

BACKGROUND: Topiramate is a novel antiepileptic drug that was licensed in Norway in 1997 as adjunctive treatment for patients with partial seizures. Metaanalysis of randomized controlled studies suggest that topiramate may be the most potent of the new antiepileptic drugs and have a favourable pharmacokinetic profile. At the National Center for Epilepsy we have used topiramate since 1990. We present our clinical experience with the drug.

MATERIAL AND METHODS: We have, retrospectively, assessed 114 adult patients, mainly with intractable partial seizures, who received topiramate as add-on treatment. Average follow-up was 2.3 years.

RESULTS: Four patients (3.5%) became seizure free. The overall seizure frequency was reduced by > 50% in 56 patients (49%). Adverse effects were observed in 82 patients (72%); in 54 patients (47%) the drug had to be withdrawn due to unacceptable side effects and/or lack of clinical effect. The most frequent side effects were weight loss, fatigue, behavioural and cognitive problems.

INTERPRETATION: Our results corroborate an impression of topiramate being an effective drug used as adjuntive therapy in patients with refractory epilepsy. Side effects can be a problem, but a low starting dose, a slow dose escalation, and topiramate used alone may reduce this problem.