Investigation of antihypertensive activity of carbopol valsartan transdermal gel containing 1,8-cineole

The purpose of this work was to develop a transdermal gel formulation for enhanced delivery of valsartan for the management of hypertension. Transdermal gels bearing valsartan, carbopol and 1,8cineole (penetration enhancer) were prepared and characterized for various parameters including in vitro skin permeation studies, pH, spreadability, viscosity, skin irritation potential and in vivo antihypertensive activity. Optimized valsartan gel formulation (VTGF9) showed highest transdermal flux (143.51 mu g/cm(2)/h), with an enhancement ratio of 4.53 when compared to control gel formulation (VTGF8). Incorporation of 1,8-cineole and ethanol in gel formulation enhance the permeation of valsartan significantly. Skin irritation and histopathological study revealed that the VTGF9 was safe, less irritant and well tolerable formulation for transdermal delivery. In vivo antihypertensive activity revealed that optimized VTGF9 was successful in reverting the rat BP to normal values in experimental hypertensive rats. Finally, it could be concluded that VTGF9 accentuates the flux of valsartan and is an efficient transdermal therapeutic system for delivery of valsartan. (C) 2013 Elsevier B.V. All rights reserved.