What is the mechanism of action of sustained release tablet ?

Answer 1

A polymer matrix that will slowly disintegrate in the proper environment (Acidic H2O) is the oldest and most common method, originating in the 1950's as the spansule, however there are other newer designs.

One new design uses a specialized permeable membrane, a specific mixture of binding agents and the active ingredient inside the membrane. The active is pulled through the membrane and into solution at a controlled rate.

Another uses an inpermeable polymer shell with a few small holes in it that allow the mixture of binders and active drug to be slowly dissolved + released at the desired rate.

There may be others, but those are the only three i know off the top of my head.

Answer 2

2

Answer 3

Polymaleic diacid-alkyl vinyl ether and polyvinylpyrrolidone are two examples of substances which are used to dissolve drugs and release them into cavities slowly. Polymers release active ingredients slowly.