The efficacy and long-term tolerability of lamotrigine in the treatment of severe epilepsy.

We report the effects of the addition of lamotrigine, a novel antiepileptic drug, to the therapy of 125 patients with severe refractory epilepsy. Forty-five patients (36%) reported adverse experiences and in 19 (15%), the drug was withdrawn. The commonest adverse experiences were diplopia, headache, ataxia, drowsiness, skin rash and deterioration in seizure control. Two patients were withdrawn for other reasons. The remaining 104 patients were followed for a mean of 11 months (range 3-27): 26 (25%) of these showed a marked improvement in seizure frequency (a 50% or more reduction when compared with the pre-trial period), but no patient was rendered seizure-free. Tolerance to the effects of the drug was not seen.