Transdermal drug delivery system: An overview

Abstract

Today three fourth of the drugs manufactured are taken orally and are not found to be effective as desired. When compared to oral route of administration, transdermal route has numerous advantages over the more traditional drug delivery systems. Drug delivery through the skin to attain systemic circulation is known as transdermal drug delivery system (TDD).TDDS are the dosage forms which involves penetration of the drug substances through the outermost layer of skin that is stratum corneum to show its therapeutic effect, where major part of drug is transported into systemic circulation. A Transdermal Patch is an adhesive patch that has a coating of medicine (drug) that is placed on the skin to deliver specific dose (drug) into the blood over a period of time. This review describes about recent advancements in TDD enhancement techniques, skin morphology & mechanism of penetration, components of Transdermal patches, types of patches, and its physicochemical methods of evaluation is described.