Hydrodynamically Balanced Gastro-Retentive Site Specific Drug Delivery System: An Innovative Approach

Conventional oral dosage forms suffer with many disadvantages. To avoid such limitations controlled release dosage forms are preferred. When these controlled release dosage forms administered by oral route retained in the stomach and release the drug in a controlled fashion continuously in gastrointestinal tract [1]. Controlled release systems also suffer with some limitations such as short gastric retention time and unpredictable short gastric emptying time, which leads to incomplete drug release in the absorption zone results into reduced efficiency of the dose administered [2]. To achieve a desirable prolonged gastric residence time, it is essential to design a site-specific controlled oral dosage form. The prolonged gastric retention of a dosage form increases the total duration of drug release, improves bioavailability, minimizes the drug loss and enhances solubility of poorly soluble drugs in gastric environment [3]. Furthermore, prolonged gastric retention time in the stomach also leads to effective local action in the upper part of the small intestine especially in the treatment of peptic ulcer. Hydrodynamically balanced gastric retentive drug delivery is an innovative approach play important role in prolonging gastric residence time by targeting site specific drug release in the upper intestine for local as well as systemic effect. Over the last few decades different kinds of gastroretentive drug delivery systems being developed. Main among these are: high density (sinking) systems that are designed to sink into the gastric fluid and settle at the bottom of stomach [4], low density (floating) systems that are designed to float on the gastric fluid causing buoyancy [5-7], mucoadhesive systems that are designed to adhere to stomach mucosa [8], unfoldable, extendable, or swellable systems that are designed to limit the emptying of the dosage forms through the pyloric sphincter of stomach [9], superporous hydrogel systems [10] and magnetic systems [11]. The current editorial focused mainly on concise information about hydrodynamically balanced site specific gastroretentive approach for orally administered controlled release dosage forms.