MSK: CALCIUM + VIT D

Question 1

CALCIUM + VIT D: INDICATIONS

Answer 1

• Osteoporosis
• CKD ( Tx + Prevent Secondary Hyperparathyroidism + Renal Dystrophy)
• Severe Hyperkalaemia (prevent life threatening arrhythmias)
• Hypocalcemia
• Vit D Deficiency

Question 2

CALCIUM + VIT D: MOA

Answer 2

• Essential for normal fxn of muscles, nerves, bone and clotting
• Controlled by PTH and VIT D = Increase serum calcium levels and bone mineralisation
• Calcitonin reduces serum calcium levels
• Osteoporosis = loss of bone mass which increases risk of fracture
• CKD = impaired phosphate excretion and reduced activation of Vit D = HYPOPHOSPHATEMIA + HYPOCALCEMIA
  => SECONDARY HYPOPARATHYROIDISM = Renal Osteodystrophy
• Hyperkalaemia = Ca2+ raises myocardial threshold potential, reduces excitability and the risk of arrhythmias
• Hypocalcemia and Vit D Deficiency

Question 3

CALCIUM + VIT D: ADVERSE EFFECTS

Answer 3

• Oral Calcium = Dyspepsia and Constipation

- IV = Cardiovascular collapse and local tissue damage

Question 4

CALCIUM + VIT D: WARNINGS

Answer 4

• Avoided in HYPERCALCEMIA patients

Question 5

CALCIUM + VIT D: IMPORTANT INTERACTIONS

Answer 5

• Reduces the absorption of many drugs including IRON BISPHOSPHONATES, TETRACYCLINES, LEVOTHYROXINE
• Administered IV, cannot be allowed to mix with Sodium Bicarb = Risk of Precipitation

Question 6

CALCIUM + VIT D: EXAMPLES

Answer 6

• Calcium Carbonate
• Calcium Gluconate
• Colecalciferol
• Alfacalcidol