A dry-powder inhaler including a body containing a dispersion chamber; a dispenser orifice through which the user inhales; a loading opening that receives a capsule containing a dose of dry powder for inhaling; and at least one movable portion that moves relative to the body between a first end position and a second end position; the dispersion chamber containing at least a portion of an empty capsule at the moment of inhalation, the at least one capsule portion swirling in the dispersion chamber during inhalation so as to disperse and/or break up the powder.