A Review on Transdermal Patches

Transdermal drug delivery system is an essential part of novel drug distribution system. The topically administered medications in the form of patches which when applied to the skin deliver the drug .For operative TDDS the drug are easily able to penetrate the skin and easily reach the target site. TDDS avoids the first pass metabolism, less frequency of administration, reduction gastrointestinal side effects.The TDDS review articles provide valuable information regarding the transdermal drug delivery systems and its evaluation process details as a ready reference for the research scientist who is involved in TDDS . Transdermal patch is a transdermal delivery system that can overcome problems in conventional drug administration, such as oral drug administration. Patches can provide controlled drug release and have advantages over oral administration, such as avoiding first-pass metabolism, increasing drug bioavailability, avoiding adverse effects on the gastrointestinal (GI) tract, minimizing patient variability, maintaining a constant drug in plasma ,and providing a stable therapeutic effect. The effectiveness of a patch is determined by the drug’s ability to release fromthe patch matrix and penetrate the stratum corneum. The methods used to make the patches are divided into single layer, multi-layer, reservoir system, and matrix system patches. The basic components of a patch are polymer matrix membrane, drug, permeation enhancer, pressure-sensitive adhesives, backing film, release liner, and plasticizer.