• Despite initial fears associated with its safety, aerosol administration by metered dose inhaler (MDI) is rapidly becoming the preferred form of bronchodilator therapy, as it has a number of advantages over oral agents. To enhance aerosol delivery and bronchodilator response, several important steps in the optimal use of an MDI have been characterized. Because many physicians are unaware of the optimal technique in employing an MDI, it is not surprising that patients frequently receive little or no instructions in its use. Furthermore, patients who have received instruction display great difficulty in adhering to the steps in the ideal use of an MDI and frequently cannot coordinate MDI actuation with inspiration. A number of auxiliary delivery systems have recently been developed and show varying success in circumventing the problems involved in patient use of MDIs.

(Arch Intern Med 1985;145:1659-1663)