We assessed bone mineral density (BMD) in 20 asthmatics who had been taking inhaled budesonide (BUD) (median daily dose 800 micrograms) for over a year, 13 of whom had taken previous courses of systemic steroids. Their results were compared with those of 20 patients receiving inhaled high-dose beclomethasone dipropionate (BDP) (median daily dose 1,000 micrograms), all of whom had received previous courses of systemic corticosteroids, and with those of 17 mild asthmatics who had never taken either inhaled or systemic steroids. Mean (standard deviation) (SD)) BMD in the patients taking BUD was 139.5 (28.6) mg/ml. This was significantly lower (p < 0.05) than in the control patients who had never taken inhaled or systemic steroids (160.4 (27.4) mg/ml). Mean BMD in the patients taking BUD did not differ significantly from that observed in patients taking BDP (127.5 (22.6) mg/ml). Although the reduction in BMD in the asthma patients taking regular high-dose BUD could have been due to previous courses of corticosteroid, the magnitude of bone loss is similar to that seen in patients taking high-dose inhaled BDP and intermittent corticosteroids.