An inhaler device for facilitating the inhalation of a medicament from a pierceable medicament capsule, the inhaler device including a body having a chamber for receiving a pierceable medicament capsule, piercing means for piercing a medicament capsule received in the chamber, an actuating member moveable relative to the body, and a plurality of cam members and a cam track. One movement of the actuating member relative to the body causes one of the cam members to move along the cam track in abutment therewith, the piercing means thereby being pressed from a retracted position to an extended position and another movement of the actuating member relative to the body causes the other one of the cam members to move along the cam track in abutment therewith so that the piercing means is pressed from an extended position towards a retracted position.