Bisphosphonate therapy for postmenopausal osteoporosis.

Bisphosphonates are agents that are potentially useful for treatment of osteoporosis. They are antiresorptive agents, increasing bone mass by decreasing the frequency of osteoclast activation or the depth of osteoclast resorption, or both. Intermittent cyclical therapy with etidronate has been shown to be effective for postmenopausal osteoporosis in two controlled studies. Several second- and third- generation bisphosphonates are undergoing active clinical trials.