A drug delivery device comprising a rotatable scale drum, a trigger member, an actuation member, a trigger spring acting on the trigger member and being energized by movement of the actuation member, as well as an end-of-dose switch adapted to be actuated by movement of the trigger member. The trigger member is adapted to be arranged in an axially supported position against the action of the energized trigger spring, and released from the axially supported position when the scale drum is rotated from a set position to an end-of-dose position, whereby the trigger member is moved axially by the trigger spring, the end-of-dose switch thereby being actuated.
