Publication:

A comparative study of anticonvulsant effect of phenytoin and lamotrigine in albino mice

Background The anticonvulsant activity of lamotrigine has been extensively studied and its role is established. Lamotrigine have shown recently to be useful in various epileptic seizures. Since antiepileptic drugs are used for longer duration, so less toxic drugs should be chosen. So, in the present study the Lamotrigine has been chosen to compare the anticonvulsant action, effectiveness, toxicity and lethal dose of the drug used in the study keeping the phenytoin as a standard drug.

Methods The present study has been carried out in the Department of Pharmacology, Darbhanga Medical College, Laheriasarai. Induction of seizure with the help of electro-convulsiometer in albino mice was done followed by the observation of the anti-convulsant activity of lamotrigine in comparison with phenytoin sodium was made. Side effects or toxicity of the drugs used (Acute neurotoxicity) was observed.

Results Lamotrigine caused lower mortality in comparison to phenytoin for the same dose ranges. The anticonvulsant properties of Lamotrigine were compared with phenytoin and the effect has been found to be satisfactory. Lamotrigine protected experimentally induced grand mal seizure and was observed to be ineffective against experimentally induced petit mal seizure. The ED 50 of Lamotrigine was found to be higher and the toxic dose was also higher in comparision with standard drugs. The protective index of lamotrigine was found to be less than that of phenytoin. Margin of safety of the drug was found to be more due to their shorter protective index than that of phenytoin.

Conclusions Lamotrigine can be used clinically as anticonvulsant in Grandmal type of epilepsy but not in Petitmal epilepsy, and has equivocal anticonvulsant effect but slightly less toxicity to phenytoin but further elaborate screening of the drug by various experiments is needed to come to a precise conclusion.