Osmotic delivery system, osmotic delivery system semimpermeable body assembly, and method for controlling delivery rate of beneficial agents from osmotic delivery systems

摘要

Osmotic delivery system semipermeable body assemblies that control the delivery rate of a beneficial agent from an osmotic delivery system incorporating one of the semipermeable body assemblies. A semipermeable body assembly or plug includes a semipermeable body which is positionable in an opening of an osmotic delivery system. The semipermeable body has a hollow interior portion having a size selected to obtain a predetermined liquid permeation rate through the semipermeable body. Because the beneficial agent in the osmotic delivery system is delivered at substantially the same rate the osmotic agent imbibes liquid which has permeated through the plug from a surrounding environment, the liquid permeation rate through the plug controls the delivery rate of the beneficial agent from the osmotic delivery system. The liquid permeation rate through a semipermeable body may be varied to control the delivery rate of beneficial agent from an osmotic delivery system by changing the thickness of the semipermeable body or by changing an amount of surface area of the semipermeable body that is exposed to liquid when the osmotic delivery system is located in a liquid environment of use.