Effect of essential oils on transdermal permeation of metoprolol succinate

Abstract

The objective of the present study was to prepare a matrix-type transdermal drug delivery system containing metoprolol succinate and to evaluate the effect of essential oils on transdermal permeation of drug. The solvent evaporation method was employed to fabricate transdermal patches of drug using HPMC K15M and Acrycoat L100 as polymers and polyethylene glycol 400 as a plasticizer. Prepared patches were subjected for evaluation of physical as well as physicochemical properties, moisture characteristics, and ex-vivo drug permeation studies. The results of physical characterization showed uniform casting and good appearance of patches. Satisfactory mechanical strength was revealed in the results of tensile strength and folding endurance. Ex-vivo permeation study indicated enhancing effect of essential oils on drug permeation through the skin. The maximum flux observed was 94 µg/cm2.hr achieved by formulation M3 containing lemongrass oil (20%). The results suggested that lemongrass oil was effective at higher concentration (20%) after 14 hrs of permeation while peppermint oil and eucalyptus oil were effective at low concentration (10%). Release kinetic suggested diffusion-controlled release of drug which followed the Korsmeyer-Peppas model. In conclusion, essential oils can be utilized as a safe and effective alternative for the permeation enhancement of drugs through transdermal delivery.