FORMULATIONOF MATRIX TYPE TRANSDERMAL PATCHES OF DILTIAZEM HYDROCHLORIDE: IN VITRO AND EX VIVO CHARACTERIZATION

Diltiazem is a calcium channel blocker, used in the treatment of hypertension, angina pectoris and some types of arrhythmia. The bioavailability of Diltiazem is 40-67% due to extensive first-pass metabolism in the liver. The transdermal administration of Diltiazem is a possible solution to overcome this problem. The aim of this investigation was to develop and evaluate matrix-type transdermal drug delivery systems of Diltiazem. The matrix-type transdermal patches of Diltiazem were prepared by solvent evaporation technique using HPMC K15, HPMC K100, ERL 100 and ERS 100 in the ratios of 1:1, 1:2 and 1:3. The FTIR studies showed drug-polymer compatibility. The prepared patches were characterized for various physicochemical parameters like weight, thickness, folding endurance, drug content, per cent moisture content per cent moisture absorption, in vitro drug release and ex vivo permeation. The maximum % drug release in 24 hrs for M2 formulation was 93.3±3.03 and showed maximum skin permeation 3691.8±19.25 µg/cm2 in the respective series but the obtained flux meets the required flux. The drug permeation kinetics followed a zero-order profile with a diffusion mechanism. The mechanical properties, tensile strength, and elastic modulus reveal that the formulations were found to be strong but not brittle. The results indicate that Diltiazem hydrochloride matrix type transdermal therapeutic systems could be prepared with the required flux having suitable mechanical properties. Keywords: Diltiazem hydrochloride, transdermal, solvent casting, diffusion, drug release