LONG-TERM TREATMENT WITH CALCITONIN IN OSTEOPOROSIS

Many studies have shown that calcitonin has beneficial effects on the clinical and biological disturbances of diseases characterized by an e xcessive bone remodelling. Several controlled clinical studies have sh own that long-term calcitonin treatment, given by parenteral or intran asal routes, exerts a beneficial positive effect on bone mass and bone turnover in established postmenopausal osteoporosis. Calcitonin thera py is particularly indicated for patients with high turnover osteoporo sis where results show a net gain of bone mineral in the axial skeleto n and a slowing of bone loss in the appendicular bones. Recently, calc itonin was shown to induce a significant reduction in postmenopausal o steoporotic vertebral fractures. Due to receptor down-regulation a res istance to the hormone may occur after 12-18 months of continuous trea tment. Reported results of long-term calcitonin treatment demonstrated that it is possible to delay or to avoid the ''resistance'' to calcit onin by the cyclical, or discontinued administration of the hormone.