Transdermal drug therapy has been one of the major research fields in the area of drug therapy for last few decades. However inspite of its large therapeutic potential market success has been limited. The most important reason being the barrier properties of Stratum Corneum. Various approaches had been tried to breach this barrier .This article briefly reviews the various approaches used to enhance transdermal penetration. Penetration enhancers represent a popular method of increasing drug flux through the skin for local or systemic activity. The article briefly introduces the properties of skin and its barrier characteristics. A classification of various penetration enhancement strategies is given. The following article explores the promise shown by electrical as well as sonicated transdermal drug transport as a novel drug delivery system. The paper details the application of various physical and chemical drugs in transdermal drug delivery. The paper also briefs on use of micro fabricated microneedles and biodegradable enhancers as a novel approach to transdermal drug delivery. The paper concludes with a brief discussion of the future prospects of transdermal penetration enhancers, which can significantly improve the present drug delivery scenario.
Keywords: Transdermal penetration enhancers, skin, iontophoresis, electroporation, sonophoresis, microneedles