Abstract

SUSTAINED RELEASE MATRIX TYPE DRUG DELIVERY SYSTEM: AN OVERVIEW

A. Rohit Kumar* and Arjun Sai Sreekar Aeila

ABSTRACT

Sustained drug release formulations are quite helpful in treating chronic diseases. Matrix tablets have been the most likely forms of sustained drug release forms given by oral route. Matrix tablets work by maintaining a constant plasma drug concentration and sustains the rate of release of drug over time and produces therapeutic action for prolonged time period. Extended release plays an important role in formulations having the shorter half-life and high dosing frequency. The matrix controls the rate of release of the drug. Retardants like hydroxy propyl methyl cellulose (HPMC), polyglycolic acid, poly methyl methacrylate are used. The drug is embedded into a matrix core of the retardant. The matrices used may be hydrophobic, bio degradable or mineral types. Different classes of polymers are used in controlling the release of drugs in matrix tablets which may be formulated by wet granulation or direct compression methods. The mechanisms involved in drug release in matrix tablets include both dissolution-controlled and diffusion-controlled. Thus, matrix tablets improve patient compliance by reducing the frequent administration of drug and produce better therapeutic efficacy.

Keywords: Sustained release, Matrix, Polymers.