SummaryTherapeutical aerosols were used in 58 patients suffering from acute and chronic dyspnea (bronchial asthma, pulmonary emphysema with or without chronic heart failure, chronic asthmatiform bronchitis, silicosis).If treatment is instituted with regularity and under medical control, one can effect improvement often on a very high degree in almost, all subjects treated. Although Aleudrine aerosols alone have yielded valuable results, Aleudrine, Novocaïne and Idrianol given together in aerosols prove to be of special efficacy, chiefly in emphysema. According to the pharmacological action of the three drugs used, release of dyspnea occurs in two ways : all three drugs induce pnoumodilatation and are probably acting synergieally ; further, when chronic circulatory insufficiency is present, improvement induced by such aerosols is also due to rise in cardiac output by both pneumodilatation (which increases the oxygen content of arterial blood) and analeptic action of Idrianol on cardiovascular system.Special mention is due to several characters of the beneficial action of such aerosols in different types of asthma. Case histories of 3 patients are also reported. Dyspnea of silicosis is also relieved by the aerosols used.It is suggested that medicamenteus aerolization may be of interest for helping to prevent silicosis in coal-miners.