A braking mechanism for a retractable safety syringe is disclosed herein. In a first embodiment, the braking mechanism is disposed about the distal end of a piston. The braking mechanism may comprise a friction material about a post attached to a piston. The friction material is displaced from a seat to a landing when the piston is traversed to a fully extended position to disengage the braking mechanism. In a second embodiment, the braking mechanism is disposed at a proximal end of a syringe body. The braking mechanism has a friction member which engages an outer surface of a rigid shaft of a plunger. The friction member is selectively pivotable to disengage the braking mechanism.