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Flashcards in Drugs for Bone Deck (20):
1

How much bone gets remodelled per year?

25% trabecular bone
3% cortical bone

2

Which bones are preferentially affected by bone remodelling?

femoral neck
vertebral bodies

3

T/F PTH affects both the activity of osteoblasts and osteoclasts

True

4

T/F Oestrogen preferentially targets osteoblasts

False, they decrease osteoclast activity

5

How does glucocorticoids affect bone cells?

increase osteoclast activity and decrease osteoblast activity

6

What is the clinical definition of osteoporosis?

reduction in bone mass more than 2.5 standard deviation below the norm for healthy 30 year old women

7

What's osteopaenia

a less severe form of osteoporosis, only 1 to 2.5 standard deviation below the norm

8

How does osteoporosis cause back pain?

Target the vertebral body, reduction in the trabecular density, leading to microfractures and pain

9

What are the three antiresorptive agents?

bisphosphonates
selective oestrogen receptor modulator
RANK-L inhibitor

10

What is bisphosponate an analogue of?

analogue of pyrophosphate, but enzyme resistant

11

Describe the pharmacokinetic of bisphosponate

incorporated into bone matrix and accumulate at the site of bone mineralisation for long periods

ingested by osteoclasts to promote apoptosis and recruitment of more osteoclasts

12

How often do you administer bisphosponate? What's the main side effect of this drug?

weekly
esophageal cancer

13

How does bisphosponate cause atypical fractures

It interrupts function of osteoclasts, hence the remodelling process of bone

14

How does oestrogen protect women from osteoporosis

promote osteoclast apoptosis
increase life span of osteoblasts and osteocytes
maintain bone mass

15

Why has oestrogen receptor modulators replaced direct oestrogen administration?

Oestrogen causes CVD and breast cancer

16

What's the action of raloxifene?

It's an oestrogen receptor modulator
agonist at oestrogen receptor in bone and CV tissues
antagonist at oestrogen receptor in mammary tissue and uterus

17

What is Denosumab

a RANK ligand inhibitor on osteoblasts, inhibiting osteoclast maturation

18

How is the action of PTH different in prolonged dose as opposed to acute dose

acute dose - activate osteoblast
prolonged - activate osteoclast

19

What is the side effect of taking anabolic calcium?

GIT disturbances

20

What are the four bone anabolic agents?

PTH
Oral calcium
Oral vit D analogues
Calcitonin