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Brand Name(s) : One-Alpha
Side Effects


Alfacalcidol should be used with caution in: children; patients with kidney problems, such as kidney stones (nephrolithiasis); patients receiving high doses of calcium, patients taking another type of medication called cardiac glycoside (medicines used to treat problems with the heart) such as digoxin.

It should not be used in: patients who are allergic (hypersensitive) to alfacalcidol or any of the other ingredients; patients who have a condition called hypercalcaemia (high levels of calcium in your blood); patients who have a condition called calcification (high levels of calcium in your body tissues); patients who have intolerance to certain sugars (oral drops)

Also see list of precautions and interactions.


Do not store above 25°C.


What is it used for?

  • Alfacalcidol is used to treat a number of conditions.
  • It belongs to a group of medicines called vitamin D analogues. It is a type of vitamin D.
  • It is used to increase the amount of vitamin D in your body. This often increases calcium levels as well which can help in treatment of certain illnesses.
  • In general this drug is used to treat diseases where the amount of calcium and phosphate (which is controlled by the level of vitamin D) in your body needs changing.
  • Benefits of being on this drug can include control of the levels of calcium and phosphate in your body.

Listed below are the typical uses of Alfacalcidol.

  • Treat and prevent bone conditions that are caused by kidney failure (osteodystrophy)
  • Treat illnesses and abnormalities affecting the parathyroid glands which make a substance called the parathyroid hormone.
  • Correct low levels of calcium in the blood of newborn babies (hypocalcaemia)
  • Treat the softening and deformity of the bones due to lack of calcium (rickets or osteomalacia)

On occasion your doctor may prescribe this medicine to treat a condition not on the above list.


How often do I take it?

  • This medication is available as a capsule (oral), drops (oral) or injection (into your vein).
  • Use this medication regularly in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told not to by your doctor.
  • It may take a few days before the full benefit of this drug takes effect.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • Alfacalcidol has no or little effect on the ability to drive or operate machinery. Consult your doctor or pharmacist for more details.

When can I stop?

  • Always complete the full course as prescribed by your doctor.


If any of these persist or you consider them severe then inform your doctor or pharmacist.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking alfacalcidol, tell your doctor or pharmacist if you are allergic to it; or to other vitamin D analogues; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist in case of: hypercalcaemia (high levels of calcium in your blood); a condition called calcification (high levels of calcium in your body tissues).

Before using this medication tell your doctor or pharmacist your medical history, especially any of the following: kidney problems such as kidney stones (nephrolithiasis), taking another type of medicines called cardiac glycoside such as digoxin

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • None known.

The elderly: alfacalcidol should be used with caution in the elderly as kidney function declines as you grow older and they therefore may be more sensitive to the side effects of this medication.

Pregnancy and breastfeeding - please ensure you read the detailed information below


The safety of alfacalcidol has not been established during pregnancy. Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


The safety of alfacalcidol has not been established in breastfeeding.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Before using this medicine, tell your prescriber of all the medicines you are taking including prescription medicines and medicines you have bought over the counter without a prescription. Tell your prescriber if you are taking vitamins or complementary remedies such as herbal products, as these can also interact with medicines.

If you are taking more than one medicine, these may interact with each other. Your prescriber may decide to use medicines which interact with each other if the benefit outweighs the risks. In these cases, the dose of your medicines may need to be adjusted or you may be monitored more closely.

The following medicines may interact with alfacalcidol:

  • Anticonvulsants: for epilepsy or fits
  • Barbiturates: for sleeping disorders
  • Cardiac glycosides, such as digoxin for heart problems
  • Colestyramine: for lowering your cholesterol level, or to help stop some types of diarrhoea or itching
  • Thiazide diuretics, often called "water tablets"

This information does not contain all possible interactions. Therefore, tell your prescriber of all the products you are using before taking this medicine.

If you have a question or want to discuss anything about your medicine, speak to your local pharmacist.


Taking too much alfacalcidol may cause the following: need to pass water (urine) more often; swelling of any part of your body; feeling thirsty; dry mouth or a metallic taste in your mouth; weakness or having pain in your muscles or bones; feeling sick or constipation.

People who have taken too much alfacalcidol, should contact their doctor or the nearest hospital emergency department immediately.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of Alfacalcidol or intentional overdose is suspected, contact your local hospital, GP or if in the UK call NHS Direct on 0845 4647.


If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

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CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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