A syringe cover (10) for providing needle retraction capabilities for a prefilled syringe, the prefilled syringe (1) including an extended needle (5) at a first distal end interconnecting a fluid cavity (6) containing a fluid to be expelled, the cover including: a chamber within the cover for receipt of the prefilled syringe a first catch (15) for engaging a syringe lip (4) on the prefilled syringe, holding the syringe in a needle extended position a translation (11) means for translating the needle from a needle extended position to a needle retracted position wherein the needle is substantially within the chamber a plunger (18) for expelling fluids from a cavity within the syringe by translation towards the distal end of the syringe, the plunger including a first (20) catch release mechanism thereon wherein upon movement of the plunger towards the distal end of the syringe, the first catch release mechanism (20) engages the first catch (15,16) to release the syringe from a needle extended position and the translation means translates the syringe to a needle retracted position.
