In a prospective, controlled, and randomized clinical trial, we examined the effects of treatment with vitamin D (1,000 IU/d), calcium (1 g/d), and ethane-1-hydroxy-1,1-diphosphonate (EHDP; 7.5 mg/kg body weight) on vertebral bone mass in fourteen asthmatics undergoing long-term treatment with systemically applied corticosteroids. The extent of steroid-induced bone loss was judged by vertebral bone density of the lumbar spine measured by dual-photon absorptiometry as well as by vertebral crush fracture incidence examined by conventional X-ray. Results of the measurements before treatment and after six mo were compared with those of an untreated control group of nineteen asthmatics. Bone density increased during the observation period by 5% in the treated group, compared with a decrease of 4.3% in the untreated control group (p < 0.01). Moreover, in the treated group no radiologically visible new fractures occurred; in the control group new fractures were observed in four patients. There were no serious side effects of the applied drugs during the 6-mo period. Therefore, the combination of EHDP, calcium, and vitamin D appears to be a useful regimen for the management of steroid-induced bone loss in adult asthmatics.