Dexamethasone isonicotinate aerosols were used for the management of 106 patients (33 men, 73 women) with bronchial asthma (mean age 32.7 years); 62 of the patients were steroid-dependent (maintenance dose 1 to 25 mg prednisone/day for 0.5 to 11 years) at the start of the study. A diary of symptoms (including consumption of antiasthmatic drugs) was kept; physical examination and measurement of pulmonary function (peak flow rate, forced expiratory volume in one second) were performed during a one-to-four week control period, as well as at various intervals (up to 14 months) after the start of corticosteroid aerosol therapy. Clinical subjective and objective improvement was accompanied by a significant increase in ventilatory function indices (e.g. the FEV1.0 rose from a control average of 55.5% of predicted to 72% after 4 weeks and 85% after 12 months). The antiasthmatic drug consumption decreased markedly. Administration of systemic steroids could be withdrawn in 49 of the 62 steroid-dependent patients (79%); in the remaining 13 the dose was only lowered. The side-effects were minor (hoarseness of the voice, oropharyngeal candidosis), and limited to a few cases. It is concluded that bronchial asthma can be successfully controlled in four fifths of the patients by very low doses of dexamethasone isonicotinate aerosols, with practically no systemic effects.