Effect of lamotrigine, levetiracetam and phenytoin on learning and memory in albino rats

Background: Epilepsy is one of the most prevalent non-communicable neurologic diseases leading to significant disability and mortality. Complaints of impaired learning and memory are common in patients of epilepsy. Antiepileptic drugs (AEDs) may further enhance this impairment. So the present study was carried out on albino rats to evaluate the effect of AEDs on learning and memory. Objective: To assess the effect of lamotrigine, levetiracetam and phenytoin on learning and memory in albino rats. Material and Methods: Albino rats of about 150 -200 gm of either sex were treated with drugs for 15 days and assessed for effect on learning behavior and again treated for next 15 days after which they were assessed for retention behavior (memory) on Morris water maze and Elevated plus maze. The data was statistically analyzed by applying MannWhitney test. Result: Phenytoin and lamotrigine caused significant impairment of learning whereas levetiracetam had no statistically significant effect on learning. Phenytoin also caused significant impairment of memory whereas lamotrigine and levetiracetam did not cause statistically significant impairment of memory. Conclusion: Learning was impaired by phenytoin and lamotrigine but not by levetiracetam which has novel mechanism of action. Phenytoin resulted in memory impairment on Morris water maze but no impairment on elevated plus maze and no other drug caused this effect.