A method for operating a dry powder inhaler, the dry powder inhaler having a dose tape having spaced apart doses of a powder pharmaceutical, each dose being in a respective sealed blister. The inhaler includes a breath actuated blister opening system that sequentially opens a blister on the tape. The method involves routing the dose tape between first and second rotating elements; spring biasing the first rotating element to turn in a first direction; holding the first rotating element from rotating against the spring biasing; and releasing the first rotating element, and allowing it to rotate a fraction of one rotation, when air flows adjacent to the first rotating element.