Described is drug infusion device. The device is intended to permit the delivery of medication over an extended period of time. An exemplary device for injecting medication may comprise: a housing a cavity configured to accept a drug cartridge a plunger configured to interact with the drug cartridge at least one biasing spring biased against an inner surface of the cavity and the plunger and an infusion device configured to carry fluid from the drug cartridge to a catheter.La présente invention concerne un dispositif de perfusion dun médicament. Le dispositif est conçu pour permettre ladministration de médicaments sur une longue période de temps.