Patent ID: 8275455

Claim:
A medical device comprising: a reservoir having an internal surface, a therapeutic-agent-containing material that comprises a therapeutic agent disposed within the reservoir, and a first electrode comprising a first conductive polymer that defines at least a portion of the internal surface of the reservoir, wherein a rate of release of the therapeutic agent from the reservoir begins or is increased upon the application of a potential that is sufficient to change the oxidation state of the first conductive polymer, wherein the conductive polymer reversibly swells or shrinks upon the change in oxidation state, (a) wherein the first conductive polymer defines at least a portion of a surface of walls of the reservoir and wherein the change in oxidation state swells the first conductive polymer, reducing the volume of the reservoir and expelling the therapeutic-agent-containing material such that the rate of release of the therapeutic agent from the reservoir begins or is increased or (b) wherein the first conductive polymer connects two opposing walls of material which form said reservoir and wherein the change in oxidation state shrinks the first conductive polymer such that the walls are drawn together, reducing the volume of the reservoir and expelling the therapeutic-agent-containing material such that the rate of release of the therapeutic agent from the reservoir begins or is increased.