A comparative study of effect of phenytoin, topiramate, and zonisamide in learning and memory of albino rats

Bhulan Prasad Loc, Kishor Chakraborty, Vineet Kumar, Manju Gari


Background: Epilepsy is one of the non-communicable neurologic diseases leading to significant morbidity 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.

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 on Morris water maze and Elevated plus maze. The data was statistically analyzed by ANOVA and Tukey HSD.

Results: Phenytoin and topiramate causes significant delay in learning and memory whereas zonisamide doesn’t causes significant delay in learning and memory.

Conclusions: Impairment in learning and memory occurs in treatment with phenytoin and topiramate but not with zonisamide in low therapeutic doses.


Learning and memory, Phenytoin, Topiramate, Zonisamide

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