An injection device for injecting a fluid into an object, the injection device including a plunger assembly for operative engagement with a syringe adapted to contain the fluid and permit ejection of the fluid therefrom via a syringe outlet, the plunger assembly being displaceable in a first direction which causes at least some of the fluid contained in the syringe to be ejected from the syringe via the syringe outlet and an inadvertent fluid ejection prevention assembly coupled to the plunger assembly for preventing ejection of fluid from the syringe in situations where the syringe outlet is neither in operative engagement with a vial adaptor suitable for providing fluid communication with the interior of a vial nor in fluid communication with an injection site within the object.