SUSTAINED RELEASE PREPARATION

摘要

The invention provides a preparation which shows a satisfactory gastric residence time, has such a size that allows for easy ingestion, can quickly disintegrate after expelled from the stomach, and can be prepared readily in an industrial scale. A gastric retentive preparation having a gastric resident layer and a drug release layer is provided, wherein the gastric resident layer does not disintegrate in the stomach and disintegrates in the intestine. Preferably, the gastric resident layer has a minimum diameter of 7 mm or more as measured after stirring the preparation in the first fluid at 200 rpm at 37° C for 15 hours under the conditions of the paddle method in the dissolution test in accordance with Japanese Pharmacopoeia and has a maximum diameter of 6 mm or less as measured after further stirring the preparation in the second fluid at 200 rpm at 37°C for 9 hours under the same conditions.