Advances and Applications of Gastro-Retentive Drug Delivery Systems

Abstract

Oral drug delivery via gastro-retentive drug delivery systems (GRDDS) has gained widespread acceptance due to its simplicity, higher patient compliance, and site-specific medication delivery. The ideal drug delivery system should allow less frequent dosing or a single dose for the entire treatment duration, with drug release directly at the site of action. GRDDS ensures controlled temporal and spatial release of medication in the stomach or upper intestinal tract, prolonging gastric retention time (GRT) and enhancing drug absorption, thus improving therapeutic efficacy and patient compliance. This paper explores various techniques employed to achieve gastro retentive drug delivery, including low-density systems, mucoadhesive systems, expandable/unfoldable systems, and high-density systems. Different types of drugs suitable for gastro retention are discussed, such as those absorbed in the upper gastrointestinal tract, drugs with local effects in the stomach, unstable drugs in the bowels or colon, and drugs for combating H. pylori in peptic ulcers. The focus is on floating drug delivery systems, classified as non-effervescent and effervescent systems. Non-effervescent systems, like Balanced Hydrodynamic Systems (HBS), utilize hydrophilic polymers to create floating bulk in the stomach, while effervescent systems produce gas to reduce density and maintain buoyancy. Mucoadhesive systems, on the other hand, form semi-permanent sticky links with the stomach wall's mucus, increasing drug retention. Overall, the development of innovative sustained-release drug delivery systems with gastro-retentive properties holds great promise for improving drug therapy from both academic and industrial perspectives.