Analytical Methods, Preformulation Study and Physicochemical Evaluation Techniques for Transdermal Patches of Antihypertensive Drug

Since early 1980s, this dosage form of transdermal therapeutic system has been available in the pharmaceutical market. The discovery of transdermal drug delivery systems (TDDS) is a breakthrough in the field of controlled drug delivery systems. The ability of TDDS to deliver drugs for systemic effect through intact skin while bypassing first pass metabolism has accelerated transdermal drug delivery research in the field of pharmaceutics. Over a decade of such extensive research activities, many transdermal patches have been developed and successfully commercialized. The present study was carried out to evaluate transdermal formulation containing carvedilol with different ratios of hydrophilic (Eudragit RL100,HPMC) and hydrophobic polymeric (Eudragit RS100,Ethyl Cellulose) combinations plasticized with triethyl Citrate and dibutyl phthalate by the solvent evaporation technique. The prepared patches were tested for their physicochemical characteristics such as thickness, weight and drug content uniformity, water vapour transmission, folding endurance, and tensile strength.In vitro release studies of carvedilol-loaded patches in 30% v/v Methanolic Isotonic Phosphate Buffer(MIPB) of pH 7.4 . The antihypertensive activity of the patches was studied using methyl prednisolone acetate induced hypertensive rats. This article describes various methods of evaluation of transdermal dosage form containing Antihypertensive drug Carvedilol.