Calcitriol is an active, man-made form of vitamin D. It is used for people with kidney disease who cannot make enough of the active form of vitamin D. It is also used to prevent and treat certain types of calcium, phosphorus, or parathyroid problems that can occur with long-term kidney dialysis or hypoparathyroidism. Calcitriol is usually used along with certain dietary recommendations and sometimes other medications.
- Trade names of the drug: Calcit, Calcijex, Ostriol, Oscal, Ostovel, Calesco, Triocol, Kolkatriol, and Rocaltrol.
- Drug Class: Vitamin D analogues.
- Category: Prescription drugs.
- Indication: Supplements vitamin D deficiency in the body.
- Pregnancy and breastfeeding categories:
Category B
This medication may be used by pregnant women. Animal studies have not shown a risk to the fetus, but there is no direct evidence in pregnant women.
- Drug form: Capsules.
Benefits of Calcitriol
Calcitriol is a form of vitamin D that helps the body absorb calcium in the stomach. It is useful in treating hyperparathyroidism (overactive parathyroid glands) and metabolic bone disease in people who have chronic kidney failure and cannot receive dialysis.
This drug can also be used to treat calcium deficiency in people with hypoparathyroidism (underactive parathyroid glands) caused by surgery, disease, or other conditions. Another benefit of calcitriol is to treat calcium deficiency (hypocalcemia) and metabolic bone disease in people receiving dialysis.
Calcitriol Dosage
The dosage given for this drug can vary from person to person. This depends on the disease experienced and the age of the person affected. Here is the division of doses that can be given:
Chronic kidney dialysis-associated hypocalcemia
- The dosage given orally:
For adults, the initial dose is 0.25 mcg orally once/every day; titrate by 0.5-1 mcg/day every 4-8 weeks.
For children, the dose given is 0.25-2 mcg/day once a day.
- The dosage given intravenously:
For adults, the initial dose is 1-2 mcg IV (0.02 mcg/kg) 3 times/week; adjust the dose every 2-4 weeks.
Maintenance: 0.5-4 mcg IV 3 times a week
Hypoparathyroidism or pseudohypoparathyroidism
The initial dose given is 0.25 mcg per day once/day; titrated by 0.25 mcg every 2-4 weeks. Then, in terms of maintenance, the dose can vary, namely:
- Adults: 0.5-2 mcg orally once daily.
- Children under 1 year: 0.04-0.08 mcg/kg orally once/day.
- Children 1-5 years: 0.25-0.75 mcg once daily/orally.
- Children over 6 years: 0.5-2 mcg once daily.
Secondary hyperparathyroidism in moderate to severe kidney disease
- Adults: 0.25 mcg/day orally and may increase to 0.5 mcg/day.
- Children under 3 years: 0.01-0.015 mcg/kg/day.
- Children 3 years and over: 0.25 mcg/day orally and may increase to 0.5 mcg/day.
How to Use Calcitriol
Take this medication by mouth with or without food, usually once daily or as directed by your doctor. The dosage is based on your medical condition and response to therapy. Your doctor may start you at a low dose and slowly adjust the dose to find the best dose.
Follow your doctor’s directions carefully. Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day.
It is very important to follow the diet recommended by your doctor to get the most benefit from this medication and to prevent serious side effects. Do not take other supplements or vitamins unless recommended by your doctor.
Certain medications, such as bile acid sequestrants such as Cholestyramine or Colestipol, mineral oil, or orlistat, can reduce the absorption of vitamin D. Therefore, separate the doses of these medications as far as possible from the doses of calcitriol.
It may be easiest to take calcitriol at bedtime if you are taking other medications at the same time. Ask your doctor or pharmacist about finding a good dosing schedule that will work with all of your medications.
Cautions in Using Calcitriol
Before taking calcitriol, tell your doctor or pharmacist if you are allergic to it; or to other vitamin D products; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
This medicine should not be used if you have certain medical conditions. Before using this medicine, talk to your doctor or pharmacist if you have high calcium levels.
Calcitriol Side Effects
Calcitriol can cause side effects such as allergic reactions, such as swelling of the face, lips, tongue or throat. In addition to these side effects, improper use of calcitriol can cause the following side effects:
- Symptoms of dehydration include feeling very thirsty or having a burning sensation in your throat, not being able to urinate, sweating a lot, or having hot, dry skin.
- High calcium levels are characterized by nausea, vomiting, constipation, increased thirst or urination, muscle weakness, bone pain, confusion, lack of energy, or feeling tired.
- Low calcium levels, characterized by muscle spasms or contractions, and numbness.
- Affects growth in children, so parents need to be aware of it.
Calcitriol Interactions
Drug interactions may change how your medications work or increase your risk for serious side effects. This does not contain all possible drug interactions. Keep a list of all the products you use and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor’s approval.
Some products that may interact with this drug include cardiac glycosides, medications containing magnesium, phosphate binders, and vitamins or nutritional supplements, medications that may speed up the removal of calcitriol from the body.
Check the labels on all prescription and nonprescription or herbal products you take because they may contain calcium, magnesium, phosphate, and vitamin D. Ask your pharmacist about using those products safely.
Calcitriol is very similar to other forms of vitamin D. Do not use medications that contain other forms of vitamin D while using this medication. This medication may interfere with certain laboratory tests, possibly causing false test results. Make sure laboratory personnel and all your doctors know that you are using this medication.
Calcitriol Contraindications
Do not take calcitriol if you have medical conditions such as:
- A person who has high levels of calcium or vitamin D in the blood.
- A person has had an allergic reaction to this drug or other forms of vitamin D.