Evaluation of Verapamil Hydrochloride Permeation Through Human Cadaver Skin

Abstract
Preformulation studies were conducted to determine the feasibility of a transdermal dosage form of verapamil hydrochloride (VPHC1). The apparent partition coefficient (octanol/water or buffer) of VPHC1 in buffers of different Ph values was determined. The saturation solubility of VPHC1 in different buffers and propylene glycol was determined. The target drug flux through the human skin to attain therapeutic concentrations in blood was determined. The maximum flux attainable through the human skin was determined. An attempt was made to increase the flux of the drug using azone as a penetration enhancer. The rate limiting barrier for the permeation of VPHC1 through the skin was determined.