A syringe has a sheath 6 covering a barrel 4, and a projection 40 sealing a channel 18, to provide a fluid seal when the sheath 6 covers the syringe. Also disclosed is a syringe with a screw thread (44, fig.1a) between a sheath 6 and barrel 4, providing a fluid seal when the sheath 6 covers the syringe. The syringes may further feature end flanges 22, and gaps 58 to reinforce the end of the syringe. The syringe may be used for the administration of a medicament to a patient body cavity.
