Reusable actuator

A reusable actuator for use with a drug container including a stopper, the reusable actuator comprising:

• a container having a closed end, an open end, and a sidewall extending therebetween in a longitudinal direction;
• an electrochemical gas-generating unit comprising an electrode, disposed at the closed end of the container and configured to generate a gas directly into an actuator interior defined in the container;
• an actuating element disposed at and closing the open end of the container,
• the actuating element being a telescopic or bellow-type structure, or being a balloon
• the actuating element being movable relative to the container in the longitudinal direction by a gas pressure generated by the electrochemical gas-generating unit,
• such that the actuating element applies a force to the stopper to cause a drug delivery from the drug container;
• and
• a retracting mechanism comprising
• (i) a valve configured to release at least a portion of the generated gas from the actuator interior, and
• (ii) a gas converting member disposed within the actuator interior and configured to chemically convert the released gas to facilitate pressure reduction,
• thereby actively assist a retraction of the actuating element for reuse.