Strontium ranelate in post-menopausal osteoporosis

Strontium ranelate is one of the first-line agents with proven anti-fracture activity used in the therapy of post-menopausal osteoporosis. Its mechanism of action makes it, however, different from other drugs, since it simultaneously stimulates two reverse processes: bone formation and bone resorption. The action of the agent depends on various mechanisms, including the activation of calcium receptors, localised on osteoblasts and osteoclasts, and on the influence on the OPG/RANKL system. The drug effectively prevents spinal, hip and extravertebral fractures. The agent's anti-fracture efficacy within the spine does not depend on the patient's age, or on base BMD values, or on the concentration of bone metabolism markers. As to the anti-fracture efficacy in the hip, it concerns women with an increased bone fracture risk. Strontium ranelate increases bone mineral density within the lumbar spine and the hip, decreases the concentrations of bone resorption markers, and increases the concentrations of bone formation markers. The drug is administered in a daily 2.0 g oral dose. This paper presents indications to therapy with strontium ranelate, specifying also its side effects and contraindications. We compare the anti-fracture efficacy of strontium ranelate to the efficacy of other agents of proven anti-fracture activity, based on published clinical studies. (Pol J Endocrinol 2011; 62 (1): 65-72)