Case studies in swelling polymeric gastric retentive tablets.

Swelling tablets administered in the fed state have been shown to provide therapeutic advantages in two marketed products, with the duration of delivery characterised with respect to food and tablet size. Metformin extended-release tablets are a diffusion-based swelling tablet demonstrating once-daily efficacy with good gastrointestinal solubility. Ciprofloxacin extended-release tablets are based on an erosional matrix that delivers the drug to the upper gastrointestinal tract over 6 h to provide once-daily efficacy with reduced incidences of nausea and diarrhoea. Furosemide extended-release tablets are another example of an erosional matrix designed to deliver furosemide to the duodenum and upper jejunum over 6 h to provide a more gradual diuresis and naturesis compared with the immediate-release product.