Along with drugs such as Estrogen and calcitonin, bisphosphonates alte
r bone remodeling by reducing bone resorption and are considered antir
esorptive agents. This article discusses several bisphosphonates that
are effective for preventing bone loss associated with estrogen defici
ency, glucocorticoid treatment, and immobilization, and for at least p
artially reversing bone loss in patients with postmenopausal osteoporo
sis and steroid-induced osteoporosis.