One-Alpha capsules, drops and injection all contain the active ingredient alfacalcidol, which is a form of vitamin D. (Alfacalcidol capsules are also available without a brand name, ie as the generic medicine.)
Vitamin D is normally obtained primarily from sunlight acting on the skin. It is also consumed in the diet in oily fish and milk products. This vitamin is converted first in the liver and then in the kidneys to its active form, calcitriol. Calcitriol acts as a hormone in the body, controlling the absorption of calcium and phosphate from the gut, the levels of calcium and phosphate in the blood and the normal healthy turnover of bone.
People who have reduced kidney function can't convert enough vitamin D into calcitriol. This can lead to problems with calcium and phosphate metabolism, reduced absorption of calcium and phosphate from the gut, low levels of calcium in the blood and various bone disorders.
Standard vitamin D supplements are no use for people with reduced kidney function, because their kidneys can't convert the vitamin into its active form. However, alfacalcidol is rapidly converted in the liver directly to calcitriol. This bypasses the step required by the kidneys and means the vitamin can then be used by the body. Taking alfacalcidol increases the amount of active vitamin D in the body, which in turn increases the level of calcium and phosphate in the blood and helps reduce bone breakdown.
Alfacalcidol is also given to provide a more rapid increase in active vitamin D and hence calcium, in people with various bone diseases. As this form of vitamin D only requires one conversion to become calcitriol, it provides a quicker response than giving normal dietary vitamin D supplements.
This medicine should not be used if you are allergic to any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.
If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
The side effects listed above may not include all of the side effects reported by the medicine's manufacturer.
For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while having treatment with this one, to make sure that the combination is safe.
Thiazide diuretics, such as bendroflumethiazide, reduce the amount of calcium excreted in the urine, and this can increase the amount of calcium in the blood. If you are taking a thiazide diuretic in combination with this medicine you should have regular blood tests to monitor the level of calcium in your blood.
People taking digoxin or other cardiac glycosides may have an increased risk of abnormal heart rhythms if they experience abnormally high blood calcium levels while taking this medicine.
The following medicines may decrease the absorption of vitamin D from the gut and should not be taken at the same time of day as this medicine:
If you are taking any of the following medicines you may need a larger than normal dose of vitamin D. Ask your doctor for advice:
Alfacalcidol capsules are also available without a brand name, ie as the generic medicine.