Osmotic releasing device having a plurality of release rate patterns

摘要: An osmotic device for releasing a useful agent at different release rate patterns from the in selected environment is disclosed. The comprised of wall surrounding and forming compartment as means containing having passageway agent. least part material permeable to an external fluid impermeable A layer pattern controlling that erodes changing carried on semipermeable distant compartment. soluble exhibits pressure gradient across against or has limited solubility admixed with osmotically effective solute fluid. In operation, released by eroding controlled increase amount available imbibition, which imbibed through into producing solution exterior permeability device.