Patent ID: 8920367

Claim:
An apparatus, comprising: a medicament container assembly coupled to a needle, the medicament container assembly including a first plunger and a second plunger, the first plunger defining, at least in part, a first volume containing a first substance, the second plunger defining, at least in part, a second volume containing a second substance; a movable assembly including a first movable member and a second movable member, the second movable member configured to move relative to the first movable member to change the movable assembly from a first configuration to a second configuration, a distal end portion of the second movable member configured to move the second plunger within the medicament container assembly when the movable assembly is changed from the first configuration to the second configuration, the first movable member configured to move the first plunger within the medicament container assembly to expel at least at least a portion of the first substance and the second substance via the needle; and a retraction mechanism configured to retract the needle, a release portion of the first movable member configured to contact the second movable member after the first movable member moves the first plunger to enable the retraction mechanism to retract the needle.