Spansules are capsules containing medicines in granules coated to release drug at different times.

• A. Ion exchange resin
• B. OROS
• C. Matrix tablet
• D. Spansules

Answer: (D)

The idea being tested is using multiple small drug units inside a capsule to control how and when the medicine is released. Spansules fit this idea exactly: a gelatin capsule filled with many coated granules, each coating designed to release the drug at its own pace. Because the granules have different coatings, the overall dose comes out over an extended period, giving staggered or sustained release from a single dose.

This works differently from the other systems. Ion-exchange resins release medication when ions in the gut swap with drug ions on the resin, not by time-controlled coatings. Osmotic release systems rely on a membrane-and-pump mechanism to push drug out at a controlled rate, not on discrete coated granules inside a capsule. Matrix tablets release drug from a single, solid swollen matrix by diffusion or erosion, rather than from multiple coated granules in a capsule.