A dispersing unit for a powder inhaler comprises a mouthpiece with an annular channel for the delivery of a stream of particles. The annular channel has an axial inlet, and an axial outlet adjoined by an annular deflection chamber in which the axially incoming stream of particles is deflected to a predominantly radial direction of flow. The deflection chamber is adjoined in the axial direction by a rotation chamber with a circular peripheral wall and an axial outlet.
