摘要：

An osmotic dispenser is comprised of (1) a water porous housing member confining (2) a first flexible bag of relatively impervious material containing an active agent and provided with active agent dispensing head, and (3) a second bag of controlled permeability to moisture containing a solution which exhibits an osmotic pressure gradient against water. The first and second bags are disposed within the housing member such that water permeates from the external environment through the housing and migrates by osmosis into the solution contained in the second bag which increases in volume thereby generating mechanical force on the first bag, which mechanical force in turn ejects the active agent out of the apparatus.

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