Safety System for a Medical Injection Device

A safety system for a medical injection device comprising a barrel containing a medical solution, a needle extending from the distal end of the barrel, and a stopper adapted to be pushed by a plunger rod for expelling the medical solution though the needle, said safety system comprising:

• a body configured for holding the medical injection device, the medical injection device being movable relative to the body between an initial distal position in which the needle protrudes distally from the body and a final safety position in which the needle is surrounded by the body, the body comprising at least one first locking member configured to releasably lock the medical injection device to the body in the initial distal position, and
• a plunger rod movable relative to the body and configured to drive the stopper in distal direction until abutment onto a distal end of the barrel, said plunger rod being axially collapsible between an initial extended configuration and a final retracted configuration,
• the plunger rod and the locking member being configured so that when the stopper abuts at the distal end of the barrel, a safety activation force exerted onto the plunger rod in distal direction collapses the plunger rod in the final retracted configuration, thereby causing the body to move to the final safety position.