Design and Evaluation of Matrix Diffusion Controlled Transdermal Patches of Coumarin

The aim of the present investigation was to prepare coumarin matrix transdermal systems using the combinations of Eudragit RL-100/Eudragit RS-100. The formulations were evaluated for various physicochemical properties (thickness, weight variation, drug content uniformity, moisture content and water absorption uptake), in vitro release studies, in vitro skin permeation studies and skin irritation studies. In vitro skin permeation and skin irritation studies were carried out on rat skin and rabbit respectively. The drug–polymer interaction results revealed no interaction between the drug and the polymers. Drug content uniformity of the patches was found more than 98%. Variations in drug permeation profiles were observed among the formulations. From the results concluded that coumarin can be formulated into the transdermal matrix type patches to overcome the first pass effect, reduced frequency of administration of coumarin and sustain its release characteristics; the polymeric composition Eudragit RL and Eudragit RS (1:1) with 1mL of ethanol was found to be the best choice for the formulation of transdermal patches of coumarin among the formulation studied.