[[Osteoporosis]] may predispose to [[vertebral compression fracture]]s which occur in 30–50% of patients on prolonged [[glucocorticoid]]s. [[Steroid]]-induced bone loss may be reversed with cyclical administration of [[etidronate]]
((Struys A, Snelder AA, Mulder H. Cyclical Etidronate Reverses Bone Loss of the Spine and Proximal Femur in Patients With Established Corticosteroid- Induced Osteoporosis. Am J Med. 1995; 99:235–242))
in 4 cycles of 400 mg/d ✖ 14 days followed by 76 days of oral calcium supplements of 500 mg/d (not proven to a reduced rate of [[vertebral fracture]]s).