Calcitonin is a bone resorption inhibitor. It exerts a central effect that helps reduce bone pain. It is administered parenterally at a starting dose of 25 units three times a week and then titrated up to 100 units subcutaneously per day. It may also be given in a nasal spray that delivers 200 units daily as a single spray. Flushing and nausea are dose-dependent side effects.
Nausea is less pronounced when the medication is delivered via the nasal route.
Estrogen is the gold standard for therapy in postmenopausal women with osteoporosis. It is an antiresorptive agent that prevents bone loss and stabilizes bone mass in patients with established osteoporosis. It is also used for fracture prevention. Fluoride is an agent that acts to increase bone formation. This is a non-standard therapy that requires more research.