Capsule (71) comprises two unilaterally open capsule elements including a capsule body (2) and a capsule cap (1), which can be telescopically plugged into each other with their openings, such that a cavity is formed, where the capsule body and/or capsule cap at least respectively have a prefabricated hole in addition to the unilateral opening. Independent claims are also included for: (1) an inhaler comprising a capsule chamber (74) for receiving the capsule, where the capsule chamber has an air inlet and an air outlet leading in the direction of a mouthpiece, and the capsule contains pharmaceutical preparation, preferably powdered preparation, and the capsule is inserted into the capsule chamber or a supply magazine, or a capsule receptacle in the capsule chamber, and a slide, where the actuating portions of the capsule are relatively moved, preferably from capsule cap to capsule body, or from annular component to capsule body and/or capsule cap, which are released to at least one prefabricated hole； (2) a system comprising inhaler and capsule, where the capsule is present in its first insertion position with respect to the telescopically inserted capsule bodies and capsule cap before actuation of the inhaler. The capsule is placed in the capsule chamber, or is introduced from the supply magazine into the capsule chamber. The inhaler comprises the slide with which the capsule can be pushed together into the capsule chamber, such that the second insertion position is reached； and (3) providing a system, comprising inserting the capsule element, which is open on one side, and the capsule body into annular component and/or capsule, filling the capsule body with a measured quantity, preferably powdery pharmaceutical composition of the capsule body, sealing with capsule cap, and assembling the annular component and/or capsule receptacle with the other components of the inhaler.
