An adapter mountable to a retractable syringe barrel comprises a body that includes a needle portion and a barrel-engaging portion and a needle aperture. The adapter facilitates mounting a needle assembly to the barrel. The needle assembly comprises a needle body and cannula and an immobile, compressible needle seal, wherein the needle body and the needle seal are releasably engaged. The needle seal is engageable with a needle portion of the adapter. The needle body comprises one or more fluid reclaim channels that facilitate efficient delivery of the fluid contents of the retractable syringe. The retractable syringe also comprises dual locking systems to impede or prevent re-use.
