Vitamin D
Indications:
• Resolve vitamin d deficiency in patients where oral supplementation is not effective or possible
• Management of hypocalcemia in patients undergoing chronic renal dialysis
• Shown to significantly reduce elevated parathyroid hormone levels. Reduction of PTH has been shown to result in an improvement in renal osteodystrophy.
• Pharmacological Effects:
– The known sites of action of calcitriol are intestine, bone, kidney and parathyroid gland
– Calcitriol is the most active known form of vitamin D3 in stimulating intestinal calcium transport
– Calcitriol has been shown to stimulate intestinal calcium absorption
– In bone, calcitriol, in conjunction with parathyroid hormone, stimulates resorption of calcium
– In the kidney, calcitriol increases the tubular reabsorption of calcium
– In vitro and in vivo studies have shown that calcitriol directly suppresses secretion and synthesis of PTH.
– Adequate vitamin D levels are associated with reduced rates of bone fracture in elderly
– Adequate vitamin D levels are associated will lower all-cause mortality rates
• Resolve vitamin d deficiency in patients where oral supplementation is not effective or possible
• Management of hypocalcemia in patients undergoing chronic renal dialysis
• Shown to significantly reduce elevated parathyroid hormone levels. Reduction of PTH has been shown to result in an improvement in renal osteodystrophy.
• Pharmacological Effects:
– The known sites of action of calcitriol are intestine, bone, kidney and parathyroid gland
– Calcitriol is the most active known form of vitamin D3 in stimulating intestinal calcium transport
– Calcitriol has been shown to stimulate intestinal calcium absorption
– In bone, calcitriol, in conjunction with parathyroid hormone, stimulates resorption of calcium
– In the kidney, calcitriol increases the tubular reabsorption of calcium
– In vitro and in vivo studies have shown that calcitriol directly suppresses secretion and synthesis of PTH.
– Adequate vitamin D levels are associated with reduced rates of bone fracture in elderly
– Adequate vitamin D levels are associated will lower all-cause mortality rates
Dose
• Deep intramuscular injection of 10,000 – 50,000 IU
(250 – 1,250 mcg) of vitamin D
Contraindications:
• Patients with hypercalcemia or vitamin D toxicity
Warning/Precautions
• Over-dosage of any form of vitamin D is dangerous
• Progressive hypercalcemia due to over-dosage of vitamin D and its metabolites may be so severe as to require emergency attention
• Chronic hypercalcemia can lead to generalized vascular calcification, nephron-calcinosis, and other soft-tissue calcification.
• Progressive hypercalcemia due to over-dosage of vitamin D and its metabolites may be so severe as to require emergency attention
• Chronic hypercalcemia can lead to generalized vascular calcification, nephron-calcinosis, and other soft-tissue calcification.
Interactions
• Concomitant use of magnesium-containing preparations should be
used with caution or avoided since such use may lead to the
development of hypermagnesemia.
• Corticosteroids with glucocorticoid activity may counteract the bone and mineral metabolism effects of vitamin D analogues.
• Cytochrome P450 enzyme-inducing anticonvulsants such as carbamazepine, phenobarbital, and phenytoin may reduce the effects of vitamin D because they increase vitamin D catabolism.
How supplied:
• 250 mcg/mL or 10,000 IU/mL IM
2500 mcg/mL or 100,000 IU/mL IM
• Corticosteroids with glucocorticoid activity may counteract the bone and mineral metabolism effects of vitamin D analogues.
• Cytochrome P450 enzyme-inducing anticonvulsants such as carbamazepine, phenobarbital, and phenytoin may reduce the effects of vitamin D because they increase vitamin D catabolism.
How supplied:
• 250 mcg/mL or 10,000 IU/mL IM
2500 mcg/mL or 100,000 IU/mL IM