Mechanism:
Inflatable systems, as the name suggests, involve dosage forms that get inflated like a balloon once they reach the stomach. These inflated structures then prevent the dosage form from passing through the pyloric sphincter, ensuring its retention in the stomach for a prolonged period.
Components:
The primary component is the drug-containing core which is enveloped by an inflatable outer shell.
The shell often contains agents that produce gas when they come into contact with gastric fluids. For example, effervescent agents such as sodium bicarbonate can be incorporated which, upon reaction with gastric acid, produce carbon dioxide. This gas inflates the system.
Types:
I. Balloon Systems:
These systems, once ingested, inflate in the stomach and maintain their buoyancy, thus preventing them from exiting the stomach through the pylorus.
II. Collapsible Capsules:
They possess a drug reservoir surrounded by an inflatable chamber. Once the chamber inflates, the capsule's opening is sealed, preventing premature drug release.
Applications:
I. Drugs with an absorption window in the upper part of the gastrointestinal tract:
Ensuring a prolonged stomach residence can be critical for drugs that have optimal absorption in the stomach or upper small intestine.
II. Controlled Drug Release:
The slow release of the drug from the inflatable system ensures a steady therapeutic effect.
III. Reduced Drug Wastage:
By retaining the drug in the desired location for longer, inflatable systems can ensure maximum drug absorption, reducing wastage and improving efficiency.
