AN OVERVIEW: GASTRORETENTIVE DRUG DELIVERY SYSTEM

Gastroretentive drug delivery systems (GRDDS) are an important area of oral controlled-release research, targeting prolonged gastric residence time (GRT) to enhance the bioavailability and therapeutic performance of drugs with narrow absorption windows, instability in alkaline pH, or requiring local gastric action. Human gastric physiology with gastric emptying increasing from 1–2 h in fasted to over 4 h in fed state, pH ranging 1.2–3.5, and migrating motor complex cycles of 90–120 min provides the basis for GRDDS development. Major approaches include floating systems (density