Abstract: An apparatus for interactive training of a patient in the use of an aerosol inhaler includes a feedback display based upon air flow versus volume data in order to train patients to use a proper sequence of inhalation steps to insure maximum delivery of an aerosol pharmaceutical to target sites in the lungs. Flow and volume data are displayed to provide the patient and physician with a real-time, interactive representation of the inhalation process. Visual feedback to the patient includes a portrayal of the lungs which may be either three dimensional or an outline form in addition to or instead of an X-Y display. An important element of visual feedback is the portrayal of the distribution of representative droplets of aerosol medication in various stages of inhalation and breath holding. Thus, the patient is provided with meaningful feedback representative of the actual distribution of aerosol medication.