The present disclosure is generally directed to a trigger mechanism for initiating dispensing doses of a medicament from a drug delivery device. The trigger mechanism includes a trigger element movable in a first direction relative to a counter element. To provide a feedback to a user of the trigger mechanism, the trigger element includes a first interference member and the counter element includes a second interference member located with respect to the first interference member such that upon movement of the trigger element relative to the counter element the first interference member contacts and passes over the second interference member, thereby generating an audible and/or tactile feedback. Further, the disclosure includes a drug delivery device for selecting and dispensing a number of user variable doses of a medicament comprising such a trigger mechanism.