**Question:** Which of the following drugs causes osteoporosis on long term use:

A. Calcium channel blockers (e.g., nifedipine)
B. Glucocorticoids (e.g., prednisolone)
C. Estrogen replacement therapy (ERT)
D. Alcohol

**Core Concept:** Osteoporosis is a condition characterized by low bone mass and microarchitectural deterioration of bone tissue, leading to increased bone fragility and susceptibility to fractures. It is a common consequence of long-term medications, lifestyle factors, or genetic predisposition.

**Why the Correct Answer is Right:** Long-term use of glucocorticoids (Option B) is a well-known risk factor for osteoporosis. Glucocorticoids are a class of corticosteroid hormones with anti-inflammatory and immunosuppressive properties. Their use leads to bone loss due to:

1. Reduced bone formation: Glucocorticoids suppress osteoblast function, reducing bone mineralization and leading to decreased bone mass.
2. Increased bone resorption: Glucocorticoids stimulate osteoclast activity, causing bone resorption and calcium release into the bloodstream.

**Why Each Wrong Option is Incorrect:**

A. Calcium channel blockers (Option A) primarily affect cardiovascular system by blocking calcium channels, reducing cardiac contractility, and lowering blood pressure. Although calcium channel blockers can cause hypocalcaemia (low blood calcium levels), they are not directly implicated in osteoporosis.

C. Estrogen replacement therapy (Option C) is used to treat menopausal symptoms and osteoporosis in postmenopausal women. However, it is not the option causing osteoporosis on its own.

D. Alcohol (Option D) consumption has been associated with reduced bone mineral density, but it is not the direct cause of osteoporosis like glucocorticoids. Alcohol can interfere with calcium absorption and increase the risk of falls, leading to fractures.

**Clinical Pearl:** Monitoring patients on long-term glucocorticoid therapy for signs of osteoporosis (e.g., decreased bone mineral density, vertebral compression fractures) is essential to initiate preventive measures and bone-protective therapies like bisphosphonates.