A holder for an inhaler article that includes a sleeve positioned within a housing cavity, a piercing element, and a lockout mechanism. The sleeve comprises a sleeve cavity arranged to receive the inhaler article. The sleeve is movable within the housing cavity between a first and second position. The piercing element is arranged to pierce the inhaler article received within the sleeve when the sleeve is moved from the first position to the second position. The lockout mechanism comprises a guide, a follower member coupled to the sleeve, and a retaining section. The follower member is arranged to move along the guide into the retaining section as the sleeve moves from the second position and back to the first position. The retaining section is arranged to hold the follower member when the sleeve has returned back to the first position, thus retaining the sleeve in the first position.