The inhalation device for medically active liquids (F) for generation of an aerosol comprises a housing (1), a reservoir (2), a pumping device with a pumping chamber (3), and a nozzle (6), wherein the interior volume of the pumping chamber (3) is changeable by means of linear relative motion of the pumping chamber to the riser pipe (5). Said linear relative motion can be effected by a relative rotation of a rotatable part (1A) which is part of, or connected to, the housing (1) with respect to a second part (1B) of said housing (1), in that said relative rotation can be transferred by means of a gear mechanism into said relative translational motion. A means for the storage of potential energy (7) is provided which is chargeable by means of said relative rotation, and wherein said energy is releasable to said pumping device when released by activation of a release means. A blocking device is provided which is adapted to block activation of the release means and/or release of the means for the storage of potential energy (7) during rotation of the rotatable part (1A) and/or during loading of the means for the storage of potential energy (7). Also, a method for the prevention of undesired emission of medically active liquid or aerosol from an inhalation device is disclosed.