Formulation and evaluation of transdermal patches of Lamotrigine

Lamotrigine is an anticonvulsant drug used in the treatment of epilepsy and bipolar disorder. Existing approved formulations of lamotrigine present cyclical plasma concentration of drug with peaks occurring after administration followed by troughs occurring before the next administration. The objective of this study was to develop a transdermal patch of lamotrigine for the better management of anti-convulsive therapy, alone or in combination. Transdermal patches were prepared by solvent casting method using HPMC, ethyl cellulose, and eudragit as the polymeric matrix. The patches were evaluated for thickness, folding endurance, % moisture content and uptake, drug content, tensile strength and in vitro permeation study. The thickness of the transdermal patches F1-F6 for different polymer ratios varied from 0.070±0.008 mm to 0.083±0.005 mm. Formulation F4 contain minimum moisture contain 1.85±0.32% and minimum moisture uptake 2.14±0.32% with a folding endurance of 220±12, and 99.94±0.52% drug content.