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Calcitriol capsules


Calcitriol is a type of vitamin D.

It is important that you follow any dietary advice you have been given by your doctor or dietician.

Make sure you know the symptoms of too much calcium in your blood - these are losing your appetite, feeling thirsty, being sick, feeling tired and losing weight. Please let your doctor know if you develop these symptoms.

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About calcitriol

Type of medicine

A type of vitamin D

Used for

To promote healthy bones

Also called


Available as


You will have been prescribed calcitriol because you have either a bone disease called renal osteodystrophy or because you have postmenopausal 'thinning' of the bones (osteoporosis). In both these conditions, calcitriol will help your body to absorb the minerals it needs and this will help to strengthen your bones.

Calcitriol is a type of vitamin D. Vitamin D helps to regulate the amount of two minerals in your body, called calcium and phosphate. All three of these substances are important for maintaining healthy, strong bones and teeth.

There are several types of vitamin D available but most other types need 'activating' by the kidneys. Calcitriol is a form of vitamin D which does not need this activation process, and so it is particularly helpful for people who need their bones strengthening but who also have kidney problems. You may also need to take mineral supplements along with calcitriol.

Before taking calcitriol

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking calcitriol it is important that your doctor knows:

  • If you are pregnant or breastfeeding.

  • If you know you have too much calcium in your blood or urine. This can happen with some cancers.

  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

  • If you have ever had an allergic reaction to a medicine.

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How to take calcitriol

  • Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about calcitriol and will provide you with a full list of the side-effects which you may experience from taking it.

  • Take calcitriol exactly as your doctor tells you to. If you have renal osteodystrophy, it is likely that you will be prescribed one dose a day, although some people may only need to take a dose on alternate days. When you first start the treatment, your doctor may give you a small dose and then gradually increase it. This allows your doctor to make sure that you have the dose that helps your condition but avoids any unwanted symptoms.

  • For 'thinning' of the bones (osteoporosis), the usual dose is one 250 nanogram capsule, twice daily.

  • Try to take your doses at the same times of day each day, as this will help you to remember to take calcitriol regularly. Swallow the capsules with a drink of water.

  • If you forget to take a dose at your usual time, take it when you remember. Try to take the correct number of doses each day, but do not take two doses together to make up for a missed dose.

Getting the most from your treatment

  • Try to keep your regular appointments with your doctor. This is so your doctor can check on your progress. Your doctor will want you to have regular blood tests to check on the amount of calcium in your blood and also on how well your kidneys are working.

  • Your doctor or dietician will discuss with you how to maintain a well-balanced and healthy diet. Please follow any advice you are given about what to eat and drink. It is important that you have plenty to drink so that you don't become dehydrated and that you don't eat foods that have been fortified with vitamin D.

  • Treatment with calcitriol is often long-term. Continue to take the capsules regularly unless you are told otherwise by your doctor.

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Can calcitriol cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The most common side-effect associated with calcitriol is due to too much calcium being in your blood. The table below contains some other common side-effects. You will find a full list of side-effects in the manufacturer's information leaflet supplied with your medicine. Please speak with your doctor or pharmacist if any of the following continue or become troublesome.

Common calcitriol side-effects (these affect fewer than 1 in 10 people)

What can I do if I experience this?

Loss of appetite, loss of weight, feeling sick (nausea), feeling thirsty, sweating, a metallic taste in your mouth, a need to pass urine more often

These are signs that there could be too much calcium in your blood. Make an appointment to see your doctor as soon as possible. Your dose may need adjusting


Drink plenty of water and ask your pharmacist to recommend a suitable painkiller. If this continues, speak with your doctor

Feeling sick (nausea), tummy (abdominal) discomfort

Stick to simple meals - avoid rich or spicy foods. If this continues, speak with your doctor, as being sick is a sign of too much calcium in your blood

Rash, urinary infections

If troublesome, speak with your doctor

If you experience any other symptoms which you think may be due to the capsules, please speak with your doctor or pharmacist for further advice.

How to store calcitriol

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

Important information about all medicines

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

If you buy any medicines, check with a pharmacist that they are suitable to take with your other medicines.

If you are having an operation or dental treatment, tell the person carrying out the treatment which medicines you are taking.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

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