Abstract

In this article various polymeric membrane systems of poly vinyl pyrrolidone, ethyl cellulose, Eudragit RS100 and ethylene vinyl acetate, containing verapamil hydrochloride, along with glycerol and dibutyl phthalate as plasticizers have been fabricated for transdermal use. Both monolithic and membrane controlled systems were prepared by the method of casting on mercury surface and evaluated for thickness uniformity, drug content uniformity, tensile strength, Percentage of elongation and skin irritation. In vitro drug permeation through rat abdominal skin and human cadaver skin was performed using Keshary-Chien diffusion cells. Results indicated that, the order of permeation of the drug from different polymeric membranes was poly vinyl pyrrolidone>ethyl cellulose>Eudragit RS100>ethylene vinyl acetate. The drug release mechanism from all monolithic systems was diffusion controlled, where as membrane controlled systems followed nearly zero order kinetics, as the thickness of rate controlling membrane was increased from 100 to 200µ, the drug release was decreased. Compared to rat skin, a low permeation rate of the drug was observed through human cadaver skin, this indicates meeting the target flux in rat skin does not guarantee it's good permeability in human skin.