Effects of lamotrigine on absence seizures in rats

Lamotrigine, a novel antiepileptic drug thought to inhibit the excitatory neurotransmitter release and indicated for convulsive seizures, was tested for its efficacy in modulating non-convulsive seizures of the absence type of epilepsy. This was done in a rat model for absence epilepsy: the WAG/Rij strain of rats. In side-effect free doses, lamotrigine did not inhibit absence seizures in these animals. Only in a high dose a reduction of spike-wave activity was noticed, but in that dose side-effects such as abnormal locomotion, were also seen. These findings underline the differential pharmacological profile of convulsive and non-convulsive generalized epilepsy.