• TRANSDERMAL DRUG DELIVERY SYSTEM-A COMPREHENSIVE REVIEW

Abstract

Transdermal drug delivery systems (TDDS), also known as “patches”, are dosage forms designed to deliver a therapeutically effective amount of drug across a patients skin. TDDS has become a proven technology that offers significant clinical benefit over other dosage forms. it provides a leading edge over injectables and oral routes by increasing patient compliance and avoiding first pass metabolism respectively. besides providing above advantages it also provides controlled, constant administration of drug, allows continuous input of drugs with short biological half-lives and eliminates pulsed entry into systemic circulation, which often causes undesirable side effects. First generation TDDS have continued their steady increase in clinical use for delivery of small, lipophilic, low-dose drug. Second generation delivery system using chemical enhancers, non-cavitational ultrasound and iontophoresis have also resulted in clinical products, the ability of ionotophoresis to control delivery rates in real time provides added functionality. Third generation delivery system targets their effects to skin’s barrier layer of stratum corneum using microneedles, thermal ablation, micro dermabrasion, electroporation and cavitational ultrasound. The advantage of TDDS is that it is painless technique of administration of drugs.