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Alfacalcidol capsules (One-Alpha®)

Patient information A-Z

What are alfacalcidol capsules and what do they do?

Alfacalcidol is one of a group of medicines called vitamin D analogues which control the levels of calcium and phosphate in your body. They are used in conditions where there is a disturbance in the body’s calcium levels, for example in kidney disorders where they are used to manage changes in the bones caused by kidney failure.

Alfacalcidol is a form of vitamin D. It is given to increase your blood calcium level and control your parathyroid hormone (PTH) levels and keep these normal.

In addition to alfacalcidol many patients will also be prescribed phosphate binders (for example Calcichew®, Renagel®) to ensure that your phosphate and calcium levels are well controlled.

Why am I prescribed alfacalcidol capsules?

When your kidneys can no longer control vitamin D themselves, the parathyroid hormone (PTH) and calcium levels in your body are affected. Alfacalcidol helps to keep these levels normal and prevent long term complications such as renal bone disease.

How do I take my alfacalcidol capsules?

Alfacalcidol is taken either daily or three times a week. Check with your doctor, pharmacist or specialist nurse to make sure you know how often you are to take your capsules – the label on the box should tell you as well.

Alfacalcidol capsules come in three strengths and the capsules are different colours. You may have to take more than one capsule to make up the correct dose.

Do I need to have any tests or be monitored because I am taking alfacalcidol capsules?

Your doctor will monitor your calcium and parathyroid hormone (PTH) levels regularly and may adjust your dose of alfacalcidol depending on your levels.

Are there any side effects?

This medicine is based on the natural active form of a vitamin and it causes no unexpected side effects. It is important however to ensure that treatment does not result in calcium levels in blood which are too high (hypercalcaemia) - your doctors will check your calcium level regularly to make sure that this does not happen.

If you are concerned that you are experiencing or have experienced a side effect that you think may have been caused by the alfacalcidol capsules please contact your doctor or specialist nurse for advice.

Special cautions when taking alfacalcidol

The One-Alpha® brand of alfacalcidol capsules contain sesame oil. They should be avoided by people suffering from rare peanut allergy. If you think that this affects you, please contact your doctor, specialist nurse or pharmacist as soon as possible.

Are there any problems taking alfacalcidol capsules with any other medications?

Some medicines used in the treatment of epilepsy (phenobarbitone, phenytoin, carbamazepine) reduce the levels of vitamin D in the body. If you are taking any of these medications your doctor will adjust your alfacalcidol dose accordingly.

Avoid vitamin supplements which contain vitamin D, including multivitamin tablets and fish oil preparations (including cod liver oil).

Only take tablets prescribed for you by your doctor and check with your pharmacist before taking any new medicines.

Further infomation

Further information about your tablet can be found in the patient information leaflet found in the tablet/capsule box or on the container.

If you have any other questions about your medication, please call the medicines helpline on 01223 217502.

We are smoke-free

Smoking is not allowed anywhere on the hospital campus. For advice and support in quitting, contact your GP or the free NHS stop smoking helpline on 0800 169 0 169.

Other formats

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Cambridge University Hospitals
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CB2 0QQ

Telephone +44 (0)1223 245151
https://www.cuh.nhs.uk/contact-us/contact-enquiries/