A. Mohan, Ghosh S.K.
Epilepsy (from the Ancient Greek word (epil??????psía) — "seizure") is a common chronic neurological disorder characterized by seizures. The mainstay of treatment of epilepsy is anticonvulsant medications. Some of the new antiepileptic drugs are: Oxcarbazepine, Lamotrizine, Topiramate, Zonisamide. All these new anticonvulsants have shown promising results in the formulation of new dosage forms such as fast dissolving tablets or buccal tablets. For these formulations it becomes important to study their permeation across the buccal membrane and if inherently permeable drugs are chosen their formulations as fast dissolving tablets will be more successful. Since the present study deals with new antiepileptics a suitable spectrophotometric method of analyzing Lamotrigine and Oxcarbazepine was not found during the course of Literature survey, hence a new method was devised and later validated as per the ICH guidelines. However for Topiramate and Zonisamide method reported in the literature survey was followed and these four drug’s permeation across bovine cheek mucosa using Franz diffusion cell was studied. Comparative Permeation evaluation of Drugs revealed that Lamotrigine and Oxcarbazepine showed permeation of 30% and 10% respectively which is much larger than that of Topiramate and Zonisamide (6% and 1.28% respectively). This enhanced permeability may be attributed to the slightly lipophilic character of both these drugs as compared to their counterparts and because of their higher permeability they are ideal candidates for the formulation of fast dissolving tablets thus improving their bioavailability.
