[Lamotrigine versus vigabatrin as an add-on therapy in refractory epilepsy: prospective study]

Lamotrigine (LTG) and Vigabatrin (VGB) has been licensed widely as adjunctive therapy for partial and secondary generalized seizures. We compared the efficiency of Lamotrigine and Vigabatrin as adjuvant therapy for 33 patients (16 male and 17 female) with drug-resistant partial epileptic seizures (simple and complex) with secondary generalization receiving combination therapy (carbamazepine--CBZ and valproic acid--VPA). Patients were enrolled if they had experienced two partial seizures (simple or complex) and one secondary generalization/month, despite combination therapy. Neurologic evaluation including CT, MRI and EEG was performed every 3 months during observation. Blood specimens for CBZ and VPA plasma concentration were obtained prior to the first LTG or VGB dose and twice a year during the treatment. The assessment of LTG and VGB effectiveness was performed in 2-month intervals during 2-3 years for vigabatrin (mean daily dose 2.0 g) and 1-2 years for Lamotrigine (mean daily dose 0.3 g). The treatment (CBZ, VPA or both) with Vigabatrin or Lamotrigine as adjunctive therapy was effective in about a half of patients with refractory epilepsy. Findings suggest that the reduction in partial seizures (simple or complex) frequency with Vigabatrin is greater than that with Lamotrigine. On the other hand, Lamotrigine seems to be more effective in patients with partial epileptic seizures with secondary generalization.