The role of calcitonin treatment in postmenopausal osteoporosis.

Synthetic salmon calcitonin (SCT) is a potent antiosteoclastic hormone with adjunctive stimulatory effects on osteoblastic function. It is capable of increasing or stabilizing bone mass in osteoporosis and thereby can lessen the risk of fractures. Treatment doses vary from 100 IU daily to 50 IU three times a week, and the duration of treatment is 2 to 5 years. SCT also exerts an analgesic effect on the skeleton that increases its beneficial effect. Side effects, which do not involve organ toxicity, are common but are usually mild and transient. More severe side effects can be managed by maneuvers such as bedtime dosing, premedication, and temporary dose reduction. Primary resistance occurs in approximately 25% of patients and secondary resistance, usually due to neutralizing antibody formation, in 10% to 20% of patients. SCT is indicated in both early and late osteoporosis and is the treatment of choice in the latter.