rPTH used in osteoporosis is –
**Core Concept**
Recombinant parathyroid hormone (rPTH) is a synthetic analogue of endogenous parathyroid hormone, which plays a crucial role in bone metabolism. rPTH is used in the treatment of osteoporosis to stimulate new bone formation and inhibit bone resorption.
**Why the Correct Answer is Right**
rPTH works by binding to parathyroid hormone receptors on osteoblasts, leading to an increase in the expression of genes involved in bone formation. This results in the deposition of new bone matrix and the formation of mineralized bone tissue. rPTH also has a dual effect on bone resorption, initially stimulating osteoclast activity and then inhibiting it, leading to a net decrease in bone resorption. This dual effect helps to promote bone formation and reduce bone loss.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not a correct description of the mechanism of action of rPTH in osteoporosis treatment.
**Option B:** This option is incorrect as rPTH is not primarily used to treat osteopenia in young individuals.
**Option C:** This option is not accurate as rPTH is not used to treat osteoporosis in patients with a history of malignancy.
**Clinical Pearl / High-Yield Fact**
rPTH is administered via subcutaneous injection, typically once or twice weekly, and is most effective when used in combination with other osteoporosis treatments, such as bisphosphonates.
**Correct Answer: C. Abaloparatide**