摘要 |
<p>An osmotic system is disclosed for dispensing a beneficial agent. The system comprises (1) a first wall of a semipermeable material that surrounds a compartment containing a drug formulation, and has a passageway through the wall for releasing agent from the compartment, (2) a second wall positioned distant from the first wall, said second wall a microporous or hydrogel material that extends around the first wall, and (3) a distribution zone interposed between the first and second wall and initially housing a compound soluble in an external fluid that enters the system. In operation, agent is dispensed from the system by fluid passing through the second wall into the zone from which fluid is further being imbibed through the first wall into the compartment forming a solution that is released through the passageway into the zone, and then through the second wall to the exterior of the system.</p> |