a drug powder inhaler has a cover plate pivotably attached to a lid on an inhaler housing . a lever is pivotably attached to the cover plate . a blister pack disk is rotatably mounted on the housing under the cover plate . a powder duct in the housing extends from a staging chamber underneath one end of the lever to an aerosolizing chamber . an actuator in the housing is pressed to shear open a blister on the blister pack disk and thereby deliver the drug dose contents of the blister into the staging chamber . a switch senses pressure in the mouthpiece and switches on a motor spinning an impeller within the aerosolizing chamber , when inhalation is detected .