Extended release dosage form

摘要

A membrane system comprising an interior wall, a fluid-permeable exterior wall surrounding the interior wall and an internal compartment defined by the membrane system, wherein fluid permeability of the interior wall is responsive to osmolarity of an osmotic core within the internal compartment are disclosed. A controlled release dosage form comprising the membrane system and a process for delivering an osmotically active formulation from an osmotic pump over an extended period of time are also disclosed.