Engineering Gastroretentive Drug Delivery Systems For Improved Oral Bioavailability

Abstract:

Oral drug delivery remains the most preferred route due to its convenience, safety, and high patient compliance. However, conventional dosage forms often fail to provide optimal therapeutic outcomes for drugs with poor bioavailability, narrow absorption windows, pH-dependent solubility, or instability in the intestinal environment. Gastroretentive Drug Delivery Systems (GRDDS) have emerged as an effective strategy to overcome these limitations by prolonging gastric residence time and enabling controlled, site-specific drug release in the upper gastrointestinal tract. This review highlights various GRDDS approaches, including floating, mucoadhesive, swelling, high-density, raftforming, and hybrid systems, along with their mechanisms, advantages, and limitations. It also emphasizes the critical role of natural and synthetic polymers in achieving buoyancy, adhesion, swelling, and sustained drug release. Recent advancements in nanotechnology, such as lipid-based nanocarriers, nanoparticles, and stimuli-responsive systems, have further enhanced the efficiency of GRDDS by improving drug solubility, stability, and targeted delivery. Additionally, emerging technologies like 3D and 4D printing offer promising opportunities for developing personalized and intelligent gastroretentive systems with consistent performance. Despite these advancements, challenges related to safety, toxicity, scalability, and regulatory compliance remain. Overall, GRDDS represent a promising and evolving platform for improving oral drug delivery, reducing dosing frequency, and enhancing therapeutic efficacy.