Gastro-retentive Drug Delivery System- An Overview

Gastro retentive drug delivery system (GRDDS) refers to systems in which the drug retained in the stomach for a prolonged period of time that improves the bioavailability of drug substances. The aim of any delivery system is to deliver a therapeutic amount of drug to the specific site in the body to obtain rapid and then maintain a requisite amount of drug. Oral controlled release drug delivery system furnishes the continuous oral delivery of drugs at predetermined and reproducible kinetics for a particular period during the course of GI transit. Various problems may arise in designing controlled release systems to improve absorption and to increase bioavailability. One of the problems is the inability to control the dosage form in the required area of the gastrointestinal tract. Additionally, the oral course has distinctive physiological issues, similar to a flighty gastric discharging rate that varies from individual to individual, a short gastrointestinal travel time (8– 12 h) and the nearness of a retention window in the upper small digestive system for some medications3. To prolong the retention of a formulation at the desired absorption site, various approaches were outlined, such as floating systems, expandable systems, bio adhesive systems and high-density systems.