An injection device is provided which includes a syringe having a discharge nozzle. The syringe is movable between a retracted position in which the discharge nozzle is contained within the housing and an extended position in which the discharge nozzle extends from the housing. A trigger is activatable to allow the contents of the syringe to be discharged through the discharge nozzle. There is also a releasable locking mechanism which, when engaged, prevents the trigger from moving into an active position. The trigger includes a first portion having a cut-out which extends from a first end of the trigger in a direction substantially parallel to the first axis. The releasable locking mechanism includes a protrusion along a second axis for communicating with the first portion of the trigger when the releasable locking mechanism is engaged and for communicating with the cut-out when the releasable locking mechanism is disengaged. Such an injection device provides improved protection against accidental activation of the trigger.
