SUSTAINED RELEASE PREPARATION

摘要

[PROBLEMS] To provide a preparation which shows a satisfactory gastric residence time, has such a size that is easy to be ingested, can be disintegrated rapidly after the excretion from the stomach, and can be prepared readily in an industrial scale. [MEANS FOR SOLVING PROBLEMS] A gastric retentive preparation having a gastric resident layer and a drug release layer, wherein the gastric resident layer is never disintegrated in the stomach and is disintegrated in the intestine. Preferably, the gastric resident layer shows the minimum diameter of 7 mm or more as measured after stirring the preparation in a first solution at 200 rpm at 37°C for 15 hours under the conditions for the paddle method in the dissolution test in accordance with Japanese Pharmacopoeia and shows the maximum diameter of 6 mm or less as measured after further stirring the preparation in a second solution at 200 rpm at 37°C for 9 hours under the same conditions.