Long-term evaluation of once daily vigabatrin in drug-resistant partial epilepsy.

The purpose of this study was to evaluate on an open basis the long-term efficacy and safety of vigabatrin in drug-resistant partial epilepsy as add-on therapy, administered on a once daily basis. Thirty-five patients entered the study. Twenty patients (57%) responded to therapy and are still on drug. This efficacy is in agreement with that seen in double-blind controlled studies on twice daily dose schedules. There did not appear to be any loss of efficacy with continued treatment at this dose regimen in patients responding favourably to the drug. The once daily dosing schedule was well tolerated and side effects were usually mild and always reversible. Vigabatrin seems to be a valuable therapeutic addition for patients with partial seizures resistant to standard anti-epileptic drugs.