APPROACHES FOR GASTRORETENTIVE DRUG DELIVERY SYSTEMS-A REVIEW

Abstract

Thepurpose of writing this review on gastro retentive drug delivery systems was tocompile the recent literature with special focus on floating drug deliverysystems (FDDS) to achieve gastric retention. FDDS are of particular interestfor drugs that are locally active and have narrow absorption window in stomachor upper small intestine, unstable in the intestinal or colonic environment,and exhibit low solubility at high pH value. It is known that differences ingastric physiology (such as, gastric pH, motility) exhibit both intra as wellas inter subject variability demonstrating significant impact on gastricretention time and drug delivery behaviour.Thus, gastroretention helps toincrease the gastric residence time and improve absorption of drugs with narrowabsorption window.  The recentdevelopments of FDDS including the pharmacokinetic and pharmacodynamic aspectsaffecting gastric retention, approaches to design single-unit and multiple-unit floating systems, advantages and limitations over the conventional drugdelivery systems, and their classification and formulation aspects are coveredin detail. This review also summarizes the studies to evaluate the performanceand application of floating systems, and applications of these systems. KeyWords: Floating matrix, gastrointestinal, gastro retentive, system, evaluation.