Needle-free injection system

摘要

A needle-free injection device (22) is described. The injection device includes a user-grippable housing (26) and a syringe assembly (28) movably secured to the housing. The syringe assembly is configured to expel injectable fluid out of a nozzle (30) upon application of pressurized gas to the syringe assembly. The injection device also includes a pressurized gas delivery mechanism disposed within the housing and configured to selectively apply pressurized gas to the syringe assembly. The pressurized gas delivery mechanism is at least partly actuated by pressing the nozzle onto an injection site so that the syringe assembly moves relative to the housing.