A syringe comprising a tubular body (11) closed at one end (12) and open at the other end (13), a plunger (14) receivable in the body (11) to define a chamber (16) of variable volume, a needle support (24) adapted to support and accommodate a hollow needle, said needle support (24) being supported from or in the wall of the body (11) and being movable In a direction substantially parallel to the main axis of the body (11) between a first position at which the needle extends from the one end of the body (11) and the interior of the needle is in communication with the chamber (16) and a second position at which the outer end of the needle is in a retracted position, said needle support (24) having a protrusion (28) which is selectively engagable with the wall of the body (11) at the first and second positions to be able to be retained at said positions and receivable through the wall of the body (11) when at the second position to be engaged with the plunger (14) to prevent axial movement of both the needle support (24) and the plunger (14) with respect to the body (11).
