Abstract: An apparatus for injecting fluid, specifically contrast media, into the vascular system of a human being or other animal. The apparatus comprises a head portion and a control unit. The head portion includes the motor and drive components, and carries a removable syringe cartridge containing the fluid. Integral with the head portion is a pressure jacket for housing the syringe cartridge, and a piston plunger for forcing the fluid out of the syringe cartridge, through a catheter and into the vascular system. The control unit includes the mechanism for selecting delivery parameters, and circuitry for controlling the delivery of the contrast media into the vascular system. Also disclosed is a syringe cartridge designed to cooperate with the apparatus for injecting contrast media.