Self-protected injection syringe

Injection syringe (100) of the type including, on the one hand, an elongate syringe body (112) comprising a tube (116) closed off at one end by a front wall (118) equipped with an injection needle (120) and open at the other end, said other end being provided with radial lugs (126), and, on the other hand, a rear actuating plunger (114) mounted so as to be displaceable inside the tube (116), the syringe being also equipped with a mobile needle protector (140) slidable along the outside of the body (112), said protector (140) being displaceable in relation to the body (112) between a retracted position, set back from the injection end (120A) of the needle (120), and an active protection position, in which the front end of the protector is situated in front of the injection end (120A) of said needle (120), characterized in that the needle protector (140) comprises, at its front end, a cylindrical portion (142) being continued rearwards by a tubular portion (144) which is cut longitudinally with two opposite slits (146) via which the radial lugs (126) protrude, said tubular portion (144) being provided with an actuating block (134) at its free end.