Amit K. Goyal
Professor and Head, Department of Pharmaceutics

Co-authors:
Goutam Rath, Ranjit Singh

ISF College of Pharmacy
Moga, India

Abstract

Topical route is the largest and easily accessible administration site for the different therapeutic entities. Although, physicochemical properties of drugs and biological barriers are limiting factors for getting therapeutic outcomes. Several approaches including excipients have been utilized to overcome drawbacks associated with this route.
This review gives an overview of different excipient on the basis of their application in topical delivery of drugs.

INTRODUCTION
The best new therapeutic entities in the world are of little value without an appropriate dosage form. Excipients are typically major components of any dosage form. These non-active substances have well defined role in the dosage form and are included for a number of reasons. Further increasing demand for drugs for their instant onset of action and greater drug efficacy is expected to drive the growth of pharmaceutical excipients.
Topical formulations for drug delivery are becoming increasingly popular because of obvious advantages including; the ability to deliver the drug to the target site, allowing a broader class of drugs to be delivered into the skin, exhibiting less inter- and intra-patient variations, improved compliance, an enhanced suitability for self administration, and easy termination of therapy at any point of time. The general acceptability of topical products by patients is very high, which is quite evident from the increasing market for topical products (3).
Despite numerous opportunities, topical drug delivery is associated with many challenges including physiochemical such as poor solubility/bioavail ...