An inhalator composed of a main body affording an inhalation conduit; a second body exhibiting a housing, into which a capsule can be at least partially inserted; the second body being rotatably coupled with the main body, and being able to rotate from an open position, in which the housing is accessible from outside for insertion of a capsule, and a closed position, in which the housing is in communication with the inhalation conduit; means for cutting off a portion of a capsule which projects from the housing during rotation of the second body from the open position to the closed position.