Oral controlled release drug delivery system and Characterization of oral tablets; A review

Oral route of drug administration is considered as the safest and easiest route of drug administration. Control release drug delivery system is used as emerging tool in the development of pharmaceuticals. The oral route is most suitable for such kind of drug delivery system due to its convenience for all age groups including both pediatric and geriatrics. There are various systems which are adopted to deliver drug in a controlled manner to different target sites through oral route. It includes diffusion controlled drug delivery systems; dissolution controlled drug delivery systems, osmotically controlled drug delivery systems, ion-exchange controlled drug delivery systems, hydrodynamically balanced systems, multi-Particulate drug delivery systems and microencapsulated drug delivery system. The systems are formulated using different natural, semi-synthetic and synthetic polymers. The purpose of the review is to provide information about the orally controlled drug delivery system, polymers which are used to formulate these systems and characterizations of one of the most convenient tablet dosage form.