Vigabatrin in the treatment of epilepsy: a long-term follow-up study.

Twenty-five adult epileptic patients who had shown a satisfactory clinical response to add-on vigabatrin under placebo-controlled conditions continued on long-term treatment for up to 47 months (median 22 months). The initially favourable therapeutic response was generally maintained throughout the observation period with an overall good clinical tolerance. No evidence of neurotoxicity was detected by multimodal evoked potentials monitoring.