Parathyroid and Metabolic Bone Modulation

Question 1

Cholecalciferol

Answer 1

• Vitamin D3 supplement
• Cheaper than metabolites
• PREFERRED

Question 2

Ergocalciferol

Answer 2

• Vitamin D2 supplement

- Not as good as D3

Question 3

Calcifediol

Answer 3

• 25-Hydroxy-Vit D3
• Bypasses need for liver hydroxylation
• Useful in liver disease

Question 4

Calcitriol

Answer 4

• 1,25-Dihydroxy-Vit D3
• Useful if patient has decreased synthesis, as from chronic renal failure
• Analogues can be used in 2ndary hyperparathyroidisim– do not induce hypercalcemia

Question 5

Dihydrotachysterol

Answer 5

Equivalent to 1-alpha-OHD3

• Must be hydroxylated at 25 position in liver
• Alternative to calcitriol (I assume when kidneys work)

Question 6

Alendronate

Answer 6

-Pyrophosphate analogue
-Bind to active sites of bone remodeling and
1-Cause osteoclast apoptosis
2-Inhibit steps of cholesterol pathway needed for osteoclast function
-ALSO- Inhibits GTPase signalling, makes binding hard for osteoclasts
-Side Effects-
1-Esophagitis
2-Bone/Joint/Muscle Pain
3-RARE- Osteonecrosis of jaw

Question 7

Risedronate

Answer 7

-Pyrophosphate analogue
-Bind to active sites of bone remodeling and
1-Cause osteoclast apoptosis
2-Inhibit steps of cholesterol pathway needed for osteoclast function
-ALSO- Inhibits GTPase signalling, makes binding hard for osteoclasts
-Side Effects-
1-Esophagitis
2-Bone/Joint/Muscle Pain
3-RARE- Osteonecrosis of jaw

Question 8

Zolendronate

Answer 8

-Pyrophosphate analogue
-Bind to active sites of bone remodeling and
1-Cause osteoclast apoptosis
2-Inhibit steps of cholesterol pathway needed for osteoclast function
-ALSO- Inhibits GTPase signalling, makes binding hard for osteoclasts
-Side Effects-
1-Esophagitis
2-Bone/Joint/Muscle Pain
3-RARE- Osteonecrosis of jaw
-One dose effective for up to a year!

Question 9

Raloxifene

Answer 9

• SERM
• Increases production of OPG (Osteoprotegrin)
• Less effective than estrogen, bisphophonates
• Less off-target effects than estrogen
• Can worsen hot flashes/ leg cramps/ THROMBOEMBOLIC DISORDERS

Question 10

Teriparatide

Answer 10

• Synthetic PTH fragment that stimulates bone formation
• Intermittent dosing causes increased osteoblast activity (continuous increases osteoclasts)
• Not recommended for longer than 24 months
• Expensive

Question 11

Calcitonin-Salmon

Answer 11

• Calcitonin with better pharmacokinetics than in a human
• Decreases serum phosphate/calcium by acting at osteoclast
• Less effective than BP, teriparatide
• Indicated in back pain
• Increased risk of malignancies– no longer recommended

Question 12

Calcium gluconate

Answer 12

• Acute calcium replacement

- Treatment of choice in severe tetany

Question 13

Calcium Carbonate

Answer 13

• Calcium Supplement

- Highest elemental calcium

Question 14

Calcium citrate

Answer 14

• Calcium Supplement
• Less pH dependent than other forms
• Recommended with PPIss or H2 antagonists on board