PROBLEM TO BE SOLVED: To provide a syringe assembly having a passive disabling system to prevent reuse.SOLUTION: According to one or more embodiments, a syringe assembly comprises a barrel, a plunger rod, a locking element, and a ramp. The plunger rod includes a proximal end with a detachable thumb press, a distal end, a main body extending between the proximal end and the distal end, and a frangible element disposed at the proximal end. In the plunger rod, the distal end of the plunger rod includes a stopper slidably positioned in fluid-tight engagement with an inside surface of a cylindrical sidewall of the barrel for drawing fluid into a chamber and driving the fluid out of the chamber by movement of the stopper relative to the barrel.SELECTED DRAWING: Figure 1
