Self-powered syringe drivers

A device for delivering a medicament into a patient's body, comprising:

• a syringe cartridge comprising a housing including a proximal end, a distal end, and defining an interior, the cartridge further comprising a piston slidably disposed within the interior for delivering a medicament within the interior through a port in the distal end;
• and
• a syringe driver comprising a plunger for advancing the piston within the interior of the housing, a source of pressurized fluid, a valve, and an actuator member coupled to the valve for selectively opening a flow path from the source to the plunger to control flow of the pressurized fluid to advance the plunger to deliver medicament from the interior of the housing at a desired flow rate during an initial stage of activation comprising delivery of the medicament,
• wherein the source of pressurized fluid comprises a canister of compressible gas, and
• wherein the valve comprises a pin received within a recess communicating with the flow path, the pin and recess configured to limit flow of the fluid along the flow path during a final stage of activation after the initial stage of activation to limit advancement of the plunger while the actuator member remains activated such that the flow path from the source to the plunger remains open, thereby limiting flow of the medicament to a maximum flow rate during the final stage.