A retractable, single use syringe (10) comprises a barrel (20), a collar (60) mounted to the barrel, a retraction spring (70), a needle mount (40) located at a needle end (23) of the barrel and a plunger (30). The plunger comprises a first plunger member (31) and a second plunger member (33) that are releasably coupled to co-operatively maintain the retraction spring in an initial compressed state. The second plunger member (33) further comprises a seal (34) to prevent fluid leakage between plunger (30) and barrel (20). After depression of the plunger to deliver the fluid contents of the syringe, the first plunger member (31) engages the needle mount (40) with needle (12) attached thereto and is rotatably uncoupled from the second plunger member (33) to allow decompression of the retraction spring (70), which forces retraction of the first plunger member (31), needle mount (40) and needle (12) engaged therewith. The first plunger member (31) and the collar (60) comprise elements that co-operatively form a disabling means that prevents or at least minimizes the likelihood of subsequent depression or withdrawal of the plunger (30). Also following retraction of the first plunger member (31), the second plunger member (33) and seal (34) remains at the needle end (23) of the barrel (20) thereby preventing refilling and re-use of the syringe.Linvention concerne une seringue rétractable à usage unique (10) comprenant un cylindre (20), un collier (60) monté sur le cylindre, un ressort de rappel (70), un support (40) daiguille situé au niveau dune extrémité (23) de laiguille du cylindre et un piston (30). Celui-ci comprend un premier élément (31) et un second élément (33) couplés de manière amovible afin de maintenir de façon coopérative le ressort de rappel dans un état initial comprimé. Le second élément (33) du piston comprend également un élément détanchéité (34) permettant dempêcher une fuite de liquide entre le piston (30) et le cylindre (20). Suite à la dépression du
