Calcitriol

Calcitriol is a synthetic version of Vitamin D3 used to treat calcium deficiency with hypoparathyroidism (decreased functioning of the parathyroid glands) and metabolic bone disease in people with chronic kidney failure.

• Calcitriol is available under the following different brand names: Calcijex and Rocaltrol.

Adult and Pediatric Dosage Forms and Strengths

Capsule

• 0.25 mcg
• 0.5 mcg

Oral solution

• 1 mcg/mL

Injectable solution

• 1 mcg/mL

Dosage Considerations – Should be Given as Follows:

Chronic Renal Dialysis Associated Hypocalcemia

Oral

• Adult, Initial: 0.25 mcg orally once/day to every other day; titrate by 0.5-1 mcg/day every 4-8 weeks
• Pediatric: 0.25-2 mcg/day orally once/day

Intravenous (IV)

• Initial: 1-2 mcg IV (0.02 mcg/kg) 3 times/week; adjust dose every 2-4 weeks
• Maintenance: 0.5-4 mcg IV 3 times/week

Hypoparathyroidism/Pseudohypoparathyroidism

• Adult, Initial: 0.25 mcg orally once/day; titrate by 0.25 mcg every 2-4 weeks
• Adult, Maintenance: 0.5-2 mcg orally once/day
• Children under 1 year: 0.04-0.08 mcg/kg orally once/day
• Children 1-5 years: 0.25-0.75 mcg orally once/day
• Children over 6 years: 0.5-2 mcg orally once/day

Secondary Hyperparathyroidism in Moderate to Severe Kidney Disease

• Adult: 0.25 mcg/day orally; may increase to 0.5 mcg/day
• Children under 3 years: 0.01-0.015 mcg/kg/day
• Children 3 years and older: 0.25 mcg/day orally; may increase to 0.5 mcg/day

Familial Hypophosphatemia, Pediatric

• Initial: 0.015-0.02 mcg/kg orally once/day
• Maintenance: 0.03-0.06 mcg/kg orally once/day
• No more than 2 mcg orally once/day

Hypocalcemia in Premature Infants

• 1 mcg once/day orally for 5 days

Vitamin D Dependent Rickets (Off-label)

• Adult: 1 mcg orally once/day
• Pediatric: 0.5 mg orally twice daily; adjust the dose to maintain normal serum calcium and parathyroid hormone (PTH) levels; after 2 years, the median dose is 0.25 mcg/day

Hypocalcemic Tetany in Premature Infants (Off-label)

• 0.05 mcg/kg intravenously (IV) once/day for 5-12 days

Administration

• The goal is to maintain serum Ca 9-10 mg/dL

Common side effects of calcitriol include:

• Abdominal or stomach pain
• Apathy
• Bone pain
• BUN and creatinine increased
• Cardiac arrhythmia
• Changes in behavior
• Constipation
• Decreased sex drive (libido)
• Dehydration
• Diarrhea
• Drowsiness
• Dry mouth
• Excessive nighttime urination
• Eye pain or redness
• Eye sensitivity to light
• Growth suppression
• Headache
• Heart rate changes (fast, slow, or uneven)
• High blood calcium (hypercalcemia)
• High blood magnesium (hypermagnesemia)
• High blood phosphates (hyperphosphatemia)
• High blood pressure (hypertension)
• High cholesterol (hypercholesteremia)
• High core body temperature (hyperthermia)
• Increased thirst
• Itching
• Loss of appetite
• Loss of height
• Lower back pain
• Metallic taste
• Muscle or bone pain
• Muscle pain or weakness
• Nausea/vomiting
• Psychosis
• Severe pain in your upper stomach spreading to your back
• Sleepiness
• Slow growth (in children)
• Urinating more than usual or changes in the amount of urine
• Weight loss

This document does not contain all possible side effects and others may occur. Check with your physician for additional information about side effects.

If your doctor has directed you to use this medication, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

Calcitriol has no known severe interactions with other drugs.

• Serious interactions of calcitriol include:
  • idelalisib
  • ivacaftor
• Moderate interactions of calcitriol include:
  • axitinib
  • crofelemer
  • dabrafenib
  • dienogest/estradiol valerate
  • efavirenz
  • elvitegravir/cobicistat/emtricitabine/tenofovir DF
  • iloperidone
  • linagliptin
  • mitotane
• Calcitriol has no known mild interactions with other drugs.

This information does not contain all possible interactions or adverse effects. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions, concerns, or for more information about this medicine.

Warnings

This medication contains calcitriol. Do not take Calcijex or Rocaltrol if you are allergic to calcitriol or any ingredients contained in this drug.

Keep out of reach of children. In case of overdose, get medical help or contact a Poison Control Center immediately.

Contraindications

• Hypercalcemia or evidence of vitamin D toxicity
• Hypersensitivity to calcitriol, other vitamin D analogues, or other ingredients

Effects of Drug Abuse

• None

Short-Term Effects

• See "What Are Side Effects Associated with Using Calcitriol?"

Long-Term Effects

• See "What Are Side Effects Associated with Using Calcitriol?"

Cautions

• Excessive vitamin D may suppress parathyroid hormone.
• Risk of hyperphosphatemia, hypercalciuria.
• Efficacy may be unpredictable in patients with malabsorption syndrome.
• Adequate dietary calcium supplementation is necessary for clinical response to vitamin D.
• Use caution in malabsorption syndrome, renal/hepatic impairment.

Pregnancy and Lactation

• Use calcitriol with caution during pregnancy if the benefits outweigh the risks. Animal studies show risk and human studies are not available or neither animal nor human studies were done.
• Calcitriol enters breast milk; it is not recommended for use while breastfeeding.