The aim of this study was to evaluate the usefulness of salmon calcitonin (sCT) in preventing corticosteroid-induced osteoporosis. Three groups of patients with sarcoidosis requiring long-term steroid therapy were followed for 2 years with yearly evaluations of vertebral cancellous mineral content (VCMC) by quantitative computed tomography. The first group (n = 18) was treated with intramuscular (i.m.) sCT for the 2-year study period; the second (n = 11) with i.m. sCT for the first 4 months and then with sCT nasal spray for 20 months; the third (n = 35) received no sCT. We observed a large mineral loss in the third group but a very slight drop of VCMC in the two groups receiving sCT. SCT nasal spray was better tolerated and as effective as i.m. injections. The action of sCT appeared extremely useful, especially in the first year of steroid therapy when corticosteroid-induced mineral loss was maximal. We conclude that sCT nasal spray is a good tool for preventing corticosteroid-induced osteoporosis.