abstract |
Sustained-release formulations which can release a water-soluble active ingredient or ingredients in zero-order manner over a long period of time, comprising: a. an inert core, b. a powder-coating layer containing a water-soluble active ingredient or ingredients, c. a powder-coating layer of practically water-repellent material, and d. a film-coating layer composed of practically pH-independent and water-insoluble film-coating material. c |