Abstract

An apparatus for dispensing drugs and other medications within the body leaves the patient ambulatory and is adapted to be entirely implanted and to dispense such substances over a long period of time, e.g., one to several years, in accordance with the actual needs of the patient. A self-powered dispensing device stores a single or plural substances in powdered, liquid, or other dispensable form and utilizes a compressible container, i.e., a bellows, for withdrawing such substances from storage and dispensing to the body. The dispensing operation may be on a fixed schedule or may be controlled by monitoring single or plural sensors implanted in the body and evaluating the sensed data in order to control both the conditions under which and the kind of dispensing which takes place. Dual dispensers and dual medication may be employed.