Sustained Release Dosage Forms: A Review

Abstract

Drug delivery system is a relatively new term used in place of dosage form to describe a system for carrying drugs. The term emphasizes the complicated nature of delivering drug in an optimal fashion. Advances made in controlled drug delivery over the past decades have been significant. Delivering drug at controlled rate, slow delivery, targeted delivery are other very attractive methods and have been pursued very vigorously. Sustained release systems maintain the rate of drug release over a sustained period. Sustained release dosage forms achieve this mostly by the use of suitable polymers, which are used either to coat granules or tablets (reservoir systems) or to form a matrix in which the drug is dissolved or dispersed (matrix systems)