Osmotically driven active agent dispenser
Patent 4016880 Issued on April 12, 1977. Estimated Expiration Date: 
April 12, 1994. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
April 12, 1994. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 2478182 3146169 3247066 3538214 3916899 Method and apparatus for introducing fluids into the body Osmotic device having microporous reservoir Patent #: 3977404 InventorsApplicationNo. 05/663665 filed on 03/04/1976US Classes:424/473, With porous, perforated, apertured, or sieved layer (e.g., dialyzing layer, microporous layer, etc.)128/832With contraceptive, spermacidal, or antifertility agentExaminersPrimary: Medbery, Aldrich F.Attorney, Agent or FirmAbstractOsmotically driven active agent dispenser for use in an aqueous environment that pumps a solution of active agent, such as a drug, at a predetermined, constant rate. The dispenser is in the form of a coated tablet comprising: a core of an osmotically effective active agent composition; and an inexpandable wall that encloses the core, has a controlled permeability to water and includes means, such as brittleness or sites of structural weakness, that is responsive to the pressure generated within the dispenser by imbibition of water from the environment by the core through the wall to form at least one, and usually many, passageways in situ in the wall through which the active agent composition in solution is pumped osmotically at a rate that is substantially dependent of the rate at which water is being imbibed into the dispenser. | |
