Chakraborty Prithviraj, Dutta Debarupa , Dey Biplab Kumar
Verapamil hydrochloride is a calcium ion influx inhibitor, which is used widely in the treatment of angina pectoris, hypertension and supraventricular tachyarrhythmias and used as conventional and sustained release dosage form. Present study is aimed at proper designing of the formulation parameters in terms of the excipient incorporation. Excipients include broadly hydrophilic and hydrophobic polymers, plasticizers and penetration enhancer. Polymers includes ethyl cellulose, hydroxyl propyl methyl cellulose K4M and polyvinyl pyrrolidone.Polyvinyl alcohol was used as to prepare backing membrane, Dibutyl phthalate was used as plasticizer and DMSO was used as transdermal penetration enhancer. After preparation of the transdermal patches, they were examined in respect to several physicochemical properties thickness, percent moisture content, percent moisture absorption, percent flatness, tensile strength, weight variation to satisfy the suitable physicochemical criteria for transdermal patch. For all the formulations, invitro release and skin permeation of the drug with and without incorporation of penetration enhancer (DMSO) through abdominal skin of albino rat were studied using Keshary-Chien diffusion cell. Formulation containing increased proportion of hydroxy propyl methyl cellulose K4M and polyvinyl pyrrolidone showed faster release of drug over a period of 24 hours where as increased proportion of ethyl cellulose produce a prolonged release of drug through transdermal route for a period of more than 24 hours. DMSO significantly increased the permeation of drug through abdominal skin of albino rat.
