What therapy mimics the effects of estrogen on bone while displaying antiestrogenic effects in other tissues?

• A. Raloxifene
• B. Bisphosphonates
• C. Calcitonin
• D. Hormone replacement therapy

Answer: (A)

Raloxifene is a selective estrogen receptor modulator (SERM) that is designed to provide the benefits of estrogen in bone health while minimizing estrogenic effects in other tissues. This dual action is particularly beneficial for postmenopausal women at risk of osteoporosis, as it helps to reduce bone resorption and increase bone density, similar to the protective effects of estrogen on bones.

In contrast, bisphosphonates primarily work by inhibiting bone resorption through the osteoclasts, but they do not mimic estrogen directly or exert selective effects on estrogen receptors. Calcitonin also does not act in the same manner as estrogen; it is involved with regulating calcium levels but lacks estrogen-like bone effects. Hormone replacement therapy provides estrogen outright, without the selective tissue targeting that Raloxifene offers. Hence, Raloxifene is distinctive for its ability to mimic estrogen's effects on bone while providing antiestrogenic benefits in the breast and endometrial tissues.