Vitamin D (ergocalciferol-D2, cholecalciferol-D3, alfacalcidol) is a fat-soluble vitamin that helps your body absorb calcium and phosphorus. Having the right amount of vitamin D, calcium, and phosphorus is important for building and keeping strong bones. Vitamin D is used to treat and prevent bone disorders (such as rickets, osteomalacia). Vitamin D is made by the body when skin is exposed to sunlight. Sunscreen, protective clothing, limited exposure to sunlight, dark skin, and age may prevent getting enough vitamin D from the sun.Vitamin D with calcium is used to treat or prevent bone loss (osteoporosis). Vitamin D is also used with other medications to treat low levels of calcium or phosphate caused by certain disorders (such as hypoparathyroidism, pseudohypoparathyroidism, familial hypophosphatemia). It may be used in kidney disease to keep calcium levels normal and allow normal bone growth. Vitamin D drops (or other supplements) are given to breast-fed infants because breast milk usually has low levels of vitamin D.
Take vitamin D by mouth as directed. Vitamin D is best absorbed when taken after a meal but may be taken with or without food. Alfacalcidol is usually taken with food. Follow all directions on the product package. If you have any questions, ask your doctor or pharmacist.
If your doctor has prescribed this medication, take as directed by your doctor. Your dosage is based on your medical condition, amount of sun exposure, diet, age, and response to treatment.
If you are using the liquid form of this medication, carefully measure the dose using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose.
If you are taking the chewable tablet or wafers, chew the medication thoroughly before swallowing. Do not swallow whole wafers.
If you are taking the rapidly-dissolving tablets, dry your hands before handling the medication. Place each dose on the tongue, allow it to dissolve completely, and then swallow it with saliva or water. You do not need to take this medication with water.
Certain medications (bile acid sequestrants such as cholestyramine/colestipol, mineral oil, orlistat) can decrease the absorption of vitamin D. Take your doses of these medications as far as possible from your doses of vitamin D (at least 2 hours apart, longer if possible). It may be easiest to take vitamin D at bedtime if you are also taking these other medications. Ask your doctor or pharmacist how long you should wait between doses and for help finding a dosing schedule that will work with all your medications.
Take this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day if you are taking it once a day. If you are taking this medication only once a week, remember to take it on the same day each week. It may help to mark your calendar with a reminder.
If your doctor has recommended that you follow a special diet (such as a diet high in calcium), it is very important to follow the diet to get the most benefit from this medication and to prevent serious side effects. Do not take other supplements/vitamins unless ordered by your doctor.
Vitamin D at normal doses usually has no side effects. If you have any unusual effects, contact your doctor or pharmacist promptly.
If your doctor has directed you to use this medication, remember that your doctor 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.
Too much vitamin D can cause harmful high calcium levels. Tell your doctor right away if any of these signs of high vitamin D/calcium levels occur: nausea/vomiting, constipation, loss of appetite, increased thirst, increased urination, mental/mood changes, unusual tiredness.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.