An Overview on Polymethacrylate Polymers in Gastroretentive Dosage Forms

Drugs with lower bioavailability need repeated dosing to reach the minimum effective therapeutic concentration in plasma. In order to retain the drug in upper part of gastro intestinal tract (GIT) which is the major absorption window for majority of drugs and also to have localized effect many advances in drug delivery were made. Researchers mainly emphasize on to get patient compliance by formulating single dose, targeted and minimal side effects dosage form. The design must give constant drug release for longer time period that could be achieved through proper selection of polymers. These approaches in dosage design may also be advantageous for local action, to prevent drug degradation, delivery of gastro-irritant, narrow absorption window drugs and to get pH dependent release throughout the GIT. Polymethacrylate polymers in different ratios are available for the above objective as they are inert materials, could stay for longer time and are resistant to body fluids. This review also discusses the physicochemical properties of different available grades along with their glass transition temperatures (Tg).