Improvement of powder inhaler, consisting of a base housing (1), snap-in capsule receptacle (2) and a moveable mouthpiece (4), this latter internally including a device (7) to open the capsule (7) containing the powdered medication, housed in a breakdown chamber (10), with air intake points (11 and 12) and an outlet (14) for air mixed with powder, with the outlet (14) being integrated with the conduit (9) of the mouthpiece (4) the above- mentioned passage (14) for the air / powder mixture located between the conduit (9) and the chamber (10) is restricted and is sufficiently long to cause two effects in the capsule (C) while it spins in the chamber (10) during inhalation: a) valve - obstruction of the passage (14) by the capsule (C), more precisely by its cylindrical part, briefly and intermittently, with such obstruction of the passage (14) being repeated at every half turn (180°) of the capsule or whenever it is aligned with the passage (14) and b) impact of the capsule (C) through suction against the roof of the breakdown chamber (10) whenever it is aligned with the passage (14) and its obstruction is complete, with this impact being sufficient to neutralize the compaction of the powder at the ends of the capsule (C) during its rotation.
