FORMULATION AND EVALUATION OF TOPICAL MICROEMULGEL LOADED WITH TERBINAFINE HCL MICROEMULSION

The aim of the present study was to investigate the potential of a micro-emulgel formulation for topical delivery of Terbinafine. Terbinafine showed highest solubility in propylene glycol among the available oil phase. Tween 80 and polyethylene glycol 400 were used as surfactant and co-surfactant respectively. Using pseudo-ternary phase diagram 1:2 ratio of surfactant: co-surfactant was selected. Using Central Composite Design thirteen formulations with varying ranges of S_mix and oil phase were prepared. Final formulation was selected on the basis of transmittance. From optimization plot it was concluded that 27.93% of S_mix and 6.51% of oil phase gave maximum transmittance. Then, optimized formulation was used to prepare final microemulgel of terbinafine. Thirteen gel formulation from varying concentration of carbopol 934 and hydroxypropylmethyl cellulose was prepared and evaluated for extrudability, spread ability, drug content, in-vitro drug release, rheological study and in-vitro antifungal activity against Teniapedis. Formulations with suitable consistencies were selected and optimization was done on the basis of drug release and ex-vivo permeation study in goat skin. Formulation with 0.45gm of carbopol 934 and 0.3gm of HPMC showed better drug release and skin permeation than other formulations. This formulation was further compared with marketed terbinafine ointment and was found to give enhanced drug release and permeation.