Bone Drugs

Question 1

Effects of VitD/calcitrol

Answer 1

Increase plasma Ca and PO4

Question 2

Effects of PTH on Ca/PO4

Answer 2

Inc plasma Ca2

Decrease PO4

Question 3

Effects of FGF23 on Ca/PO4

Answer 3

Dec plasma PO4

No effect on Ca

Question 4

Why is Ca maintained at higher levels in the body?

Answer 4

Hypocalcemia is super dangerous vs hypercalcemia and can be more easily attained –> maintain Ca at the expense of PO4

Question 5

How does estrogen relate to osteoporosis?

Answer 5

Inc osteoblasts, dec osteoclasts

Inc OPG, dec RANKL

Question 6

What is the role of RANKL?

Answer 6

Activates osteoclasts

Question 7

What is the role of OPG?

Answer 7

Inhibits the production of osteoclasts

Question 8

2 phases of bone loss

Answer 8

Loss of trabecular bone

Thinning of cortical bone

Question 9

Menopause related vs age related bone loss

Answer 9

Menopause: first, 3-5 yr, trabecular bone deteriorate
Age: second, 10-20 yr, trabecular and cortical loss

Question 10

How do steroids cause osteoporosis?

Answer 10

dec in osteoblast activity, dec GI absorption of calcium

Question 11

how does excess thyroid hormone cause osteoporosis?

Answer 11

Inc bone turnover and bone loss (since bone formation takes 5x longer than resorption)

Question 12

Prevention strategies for at risk women

Answer 12

Daily Ca/VitD
Avoid weight loss/low BMI
Physical activity
Stop smoking
Fall prevention

Question 13

How does daily Ca help osteoporosis

Answer 13

Dec PTH and therefore bone resorption

Question 14

How does Vit D dec osteoporosis

Answer 14

Inc GI absorption of Ca
Inc type 2a muscle fibers
Dec PTH and therefore resorption

Question 15

How does weight bearing exercise help osteoporosis

Answer 15

reduce falls

osteocytes respond to mechanical stress to inc bone mass

Question 16

How does smoking worsen osteoporosis

Answer 16

Dec GI Ca absorption
Inc bone loss
Inc liver induction of estrogen metabolism (HRT less effective)

Question 17

Osteoporosis in cortical vs trabecular bone

Answer 17

Remodel/yr: 25% trabecular, 3% cortical (trabecular more affected in osteoporosis)

Question 18

M/c fractures

Answer 18

Vertebral > hip > limb

Question 19

First line pharm for osteoporosis

Answer 19

Bisphosphonates

Denosumab

Question 20

Which drugs are the only bone FORMING agents?

Answer 20

Teriparatide, intact PTH

Question 21

Ca supplements AE, contra

Answer 21

AE: constipation, urolithiasis, prostate cancer, GI
Contra: hypercalcemia, VFib

Question 22

Vit D supplements (calciferol, diol, triol)

Answer 22

AE: may cause more hypercalcemia
Contra: hyper Ca, Vit D, or malabsorption syndrome

Question 23

Teraparatide use, AE, Contra

Answer 23

Use: Osteoporosis w/ high fx risk
AE: angina, hypotension
Contra: paget’s, open epiphyses, prior radiation or bone malig

Question 24

Cinacalcet MOA, AE, contra

Answer 24

MOA: inc Ca sensitivity in parathyroid cells (less PTH release)
AE: arrhythmia, CHF, seizure, electrolyte
Contra: hypocalcemia

Question 25

Raloxifene MOA, AE, contra

Answer 25

MOA: SERM, agonist in bone
AE: retinal occlusion, VTE
Contra: preg, hx of VTE

Question 26

Bisphosphonates (-dronate) AE, other notes

Answer 26

AE: arthralgia, myalgia, esophageal ulcer, GI upset
Other: need good kidneys, drug holiday after 5 yrs, flu like sx with initiation

Question 27

Denosumab MOA, AE, contra

Answer 27

MOA: MAB against RANKL
AE: endocarditis, cellulitis, pancreatitis
Contra: hypocalcemia, preg

Question 28

Calcitonin use, MOA, AE

Answer 28

Use; Hypercalcemia, Paget’s dz, osteoporosis
MOA: lowers blood Ca levels by dec Gi absorption, kidney reabsoption and Ca deposition in the bone
AE: hypokalemia, seizure, cancer