The influence on the adrenocortical function of high-dose topical glucocorticoids inhaled via conventional devices and via a Nebuhaler, was studied in ten children with asthma. In patients treated with dosages of beclomethasone dipropionate or budesonide, in excess of 2100 micrograms/1.73 m2 body surface, the 24-h urinary excretion of free cortisol increased when the inhaler device was changed from a conventional one to a Nebuhaler. This suggests a decreased systemic influence of the inhaled glucocorticoids when these were administered via a Nebuhaler.