Lamotrigine: A Review of Antiepileptic Efficacy

Summary: Lamotrigine (LTG) is a chemically novel anti-epileptic drug (AED) that blocks voltage-sensitive sodium channels, leading to inhibition of neurotransmitter release, principally glutamate. LTG is active in a wide range of pharmacologic models of epilepsy, demonstrating a potency and duration of action generally superior to currently available AEDs. Preliminary evidence of efficacy was provided by single-dose studies showing effects on reducing interictal spike activity and photoconvulsive response. A total of eight randomized, double-blind, placebo-controlled, crossover trials have established the efficacy of LTG in patients with refractory partial epilepsy. Literature reports suggest LTG also is effective in patients with idiopathic generalized epilepsy, including absence seizures, and in patients with Lennox-Gastaut syndrome. Other reports suggest that LTG is useful in the pediatric population, and an interim report of an open monotherapy trial suggests that the efficacy of LTG was comparable to that of carbamazepine (CBZ) but the adverse experiences leading to discontinuation were less frequent.