Apart from the therapy of autoimmune diseases, corticosteroids have an important position in the treatment of rheumatoid arthritis. Corticosteroids are used after the failure of non-steroidal antiinflammatory agents or of the basis therapies to control the illness. When the rheumatoid arthritis is accompanied by a systemic disease, they will be used earlier and in higher dosages. For polymyalgia rheumatica, independently of an association with temporal arteritis, corticosteroids are the therapy of choice. Risks of long-time corticosteroid therapy are a higher incidence of infection and bone demineralisation, especially in postmenopausal women. A careful prevention with Calcium and Vitamin D must be carried out systematically. The demineralisation can be limited by the use of Deflazacort, a corticosteroid, which decreases the loss of calcium.