| 摘要 |
<p>An oral preparation composed of a core comprising a principal agen and a pharmaceutically acceptable filler; the first layer covering the core, which comprises an enteric or water-soluble component and may optionally contain an insoluble component; the second layer covering the first layer, which comprises a nonenteric component which dissolves by reacting with at least one component of the core; and the third layer covering the second layer, which comprises an enteric component. This preparation will not release the principal agent until it reaches a desired region in an intestine and it can release the agent at a controllable rate once it reaches that region. Thus it can be effectively used in administering a principal agent having an absorption specificity at a particular region in the intestine or treating a disease at a particular region in the intestine.</p> |
