System and method for safety syringe

A system for injecting medicine into a patient, comprising:

• a syringe body defining an interior medicine chamber having a proximal end and a distal end;
• a stopper member configured to be inserted into the interior medicine chamber to contain medicine within the interior medicine chamber;
• a plunger member having a plunger housing, and configured to be manually manipulated to insert the stopper member relative to the syringe body, the plunger member comprising an energy storage member having a first stored mode and a second released mode;
• a needle having proximal and distal ends, the proximal end comprising an anchoring geometry configured to at least partially penetrate the stopper member such that inserting the stopper member to the distal end of the interior medicine chamber causes the needle to be pulled proximally through the stopper member to be at least partially contained within the interior medicine chamber;
• a latching member having a latched mode and an unlatched mode respectively corresponding to the first and second modes of the energy storage member, wherein triggering the latching member from the latched mode to the unlatched mode results in an audible cue that signifies the latching member has been triggered and the needle has been retracted;
• and
• an unlatching member configured such that the needle proximal end moving the unlatching member causes the energy storage member to move from the first mode to the second mode,
• wherein the stopper member is a conventional off-the-shelf compliant stopper comprising an unmodified solid compliant member having a distally facing surface formed from one material that is continuous from one side of an interior of the syringe body, across a center of the distally facing surface, to an opposite side of the interior of the syringe body, with no recesses or projections in the distally facing surface.