Gastroretentive drug delivery systems: A holy grail in oral delivery

Gastroretentive drug delivery systems (GRDDSs) offer a promising strategy for enhancing oral drug bioavailability by prolonging gastric residence time and enabling site-specific drug release. This review examines the key materials used in GRDDSs, including polymers for controlled drug release, gas-generating agents for buoyancy, and mucoadhesive components for improved retention and stability. Advances in fabrication techniques, such as 3D printing, spray drying, and nanoparticle encapsulation, have enabled precise modulation of drug release kinetics and retention properties. However, challenges such as inter-subject variability, physiological constraints, and manufacturing scalability remain. Future research will focus on smart materials, multi-drug platforms, and expanding applications to biologics and nutraceuticals, paving the way for more effective and patient-compliant oral drug delivery systems.