Drugs

Question 1

What are the two categories of drugs used in bone disorders?

Answer 1

Antiresorptive agents and anabolic agents

Question 2

What are bisphosphonates?

Answer 2

Inhibit the recruitment of osteoclasts and promote apoptosis of osteoclasts
- they are incorporated into the bone matrix and ingested by osteoclasts during bone resorption

Poorly absorbed, adverse GI effects

Question 3

What is the function of oestrogen as a drug in bone disorders?

Answer 3

Decreases bone resorption by decreasing osteoclast proliferation, differentiation and activation and promotes osteoclast apoptosis
- it also increase the lifespan of osteoblasts and osteocytes

BUT associated with an increased risk of CV disease and breast cancer

Question 4

What are oestrogen receptor modulators (SERMs)?

Answer 4

Have replaced HRT in treatment of osteoporosis
- eg Raloxifene, agonist at oestrogen receptors in bone and CV tissue and antagonist at oestrogen receptors in mammary tissue and uterus

Question 5

What is denosumab?

Answer 5

Human monoclonal antibody that binds RANK-L and inhibits its activity
- reduces osteoclastic differentiation, survival and activity

Question 6

What is strontium ranelate?

Answer 6

A dual action bone agent - anti-resorptive and anabolic

- increased risk of MI, so last line of treatment, only with severe osteoporosis

Question 7

How does PTH work as an anabolic agent?

Answer 7

Acutely promotes osteoblast development and activity but continuous or high exposure promotes osteoclast activity