Controlled release dispenser comprising beneficial agent

摘要

A dispenser is disclosed for delivering a beneficial agent in a hydrophilic carrier formulation to an animal in a rate-controlled manner. The dispenser comprises (1) a semipermeable housing defining an internal space, (2) at least one composition comprising a beneficial agent and a pharmaceutically acceptable hydrophilic carrier in the space, (3) an expandable hydrophilic driving member in the space, (4) a density member in the space, and (5) one exit passageway or a multiplicity of exit passageways in the housing for delivering the beneficial agent from the dispenser, the diameter of each exit passageway being of a size to maximize release of the beneficial agent by osmotic pumping and to minimize release of the beneficial agent by diffusion or erosion to substantially avoid mechanical agitation-dependent release of the beneficial agent.