Patient/caregiver was instructed upon therapeutic uses of calcitriol as follows:

Vitamin D deficiency

• In individuals with compromised liver and kidney functions, calcitriol synthesis can be compromised.
• Deficient calcitriol synthesis results in poor calcium absorption from the intestines and reduced mineralization of bone.
• Calcitriol can be given as a supplement in these individuals to prevent long-term calcium deficiency and poor mineralization of bone.

Chronic renal failure

• In individuals with chronic renal failure, calcitriol synthesis is compromised, thus leading to poor calcium absorption from the intestines and low serum calcium levels.
• Also, poorly functioning kidneys cannot excrete phosphorus normally and consequently build-up excessive levels of phosphorus in the blood.
• This elevated serum phosphorus along with low serum calcium can stimulate excessive synthesis and secretion of parathyroid hormone.
• Increased parathyroid hormone secretion results in resorption of the bone and consequently, leads to mobilization of calcium and phosphorus from the bone into the blood, thus helping to offset the low levels of serum calcium.
• This mobilization of calcium from bone into the blood can lead to weakening of skeletal structures and osteoporosis.
• Calcitriol can be given as a supplement in these individuals to increase intestinal absorption of calcium and phosphorus from the food sources and also, to help with reabsorption of calcium in the kidneys, thus helping to restore optimal concentrations of serum calcium.
• Compliance with dialysis schedule can help with elimination of excess phosphorus.
• This restoration of calcium and phosphorus levels in the blood, secondary to calcitriol administration and compliance with dialysis schedule, can lead to inhibition of parathyroid hormone secretion, with consequent inhibition of bone resorption and osteoporotic bone changes.