A retractable safety syringe is provided herein wherein an external vacuum compartment produces a retraction force which urges a piston of a plunger toward a retracted position. The retractable safety syringe may have a needle holder which is removably engageable to a distal portion of a syringe body. When the piston is traversed toward the engaged position, the external variable vacuum compartment produces a retraction force. When the piston is traversed to an engaged position, the piston engages the needle holder and disengages the needle holder from the syringe body. The medical professional may release a thumb pressure on a thumb platform of a plunger. At this point, the retraction force of the external variable vacuum compartment may traverse the piston along with the needle holder and needle toward the retracted position and into the syringe body. An internal variable vacuum compartment may also create a retraction force to assist retraction of the needle holder and needle into the syringe body.