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Vitamin D2

Generic name: ergocalciferol (vitamin D2)ER-goe-kal-SIF-e-role ]
Brand names: Calcidol, Calciferol, Drisdol, Vitamin D2
Drug class: Vitamins

Medically reviewed by Drugs.com on Oct 3, 2023. Written by Cerner Multum.

What is ergocalciferol?

Ergocalciferol is vitamin D2. Vitamin D helps your body absorb calcium.

Ergocalciferol is used to treat hypoparathyroidism (decreased functioning of the parathyroid glands).

Ergocalciferol is also used to treat rickets (softening of the bones caused by vitamin D deficiency) or low levels of phosphate in the blood (hypophosphatemia).

Ergocalciferol may also be used for purposes not listed in this medication guide.

Warnings

You should not take ergocalciferol if you have had an allergic reaction to vitamin D, or if you have high levels of calcium or vitamin D in your body, or any condition that makes it hard for your body to absorb nutrients from food (malabsorption).

Use only the recommended dose of ergocalciferol. An overdose could cause serious or life-threatening side effects.

Before taking this medicine

You should not take ergocalciferol if you have had an allergic reaction to vitamin D, or if you have:

Tell your doctor if you have ever had:

Certain forms of ergocalciferol may contain ingredients you should know about, such as peanut or soybean oil, sugar, aspartame (phenylalanine), or certain food dyes. Ask a doctor before using ergocalciferol if you have allergies, diabetes, or phenylketonuria (PKU).

Too much vitamin D could harm an unborn baby, and your dose needs may be different during pregnancy. Tell your doctor if you are pregnant or if you become pregnant while taking ergocalciferol.

Ergocalciferol can pass into breast milk and may cause side effects in the nursing baby. Tell your doctor if you are breast-feeding.

Do not give ergocalciferol to a child without medical advice. Your child's dose will depend on age, weight, diet, and other factors.

How should I take ergocalciferol?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use only the recommended dose of ergocalciferol.

It may be best to take ergocalciferol after a meal, but you may take Vitamin D2 with or without food.

Measure liquid medicine carefully. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

You will need frequent medical tests.

Your doctor may begin to reduce your ergocalciferol dose as your condition improves. Carefully follow all instructions about adjusting your dose. In some cases, there may be a very small difference in amount between safe and dangerous doses of this medicine.

Your doctor will determine how long to treat you with this medicine.

Ergocalciferol may be only part of a complete program of treatment that also includes dietary changes and taking calcium and vitamin supplements. Follow your doctor's instructions very closely.

Learn about the foods you should eat to make sure you get enough calcium and vitamin D in your diet. Your ergocalciferol dose may need to be adjusted as you make changes to your diet.

Store at room temperature away from moisture, heat, and light.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of vitamin D can cause serious or life-threatening side effects.

Overdose symptoms may include nausea, loss of appetite, thirst, urinating more or less than usual, body aches, stiffness, confusion, or irregular heartbeats.

What should I avoid while taking ergocalciferol?

Ask a doctor or pharmacist before taking any multivitamins, mineral supplements, or antacids while you are taking ergocalciferol.

Ergocalciferol side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop taking Vitamin D2 and call your doctor at once if you have:

Less serious side effects may be more likely, and you may have none at all.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect ergocalciferol?

Certain medications can make it harder for your body to absorb vitamin D. If you take other medications, take them at least 2 hours before or 2 hours after you take ergocalciferol.

Tell your doctor about all your other medicines, especially:

This list is not complete. Other drugs may affect ergocalciferol, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Popular FAQ

Generally, it takes a few weeks of taking daily vitamin D supplements for vitamin D levels in the body to rise. Each 1,000 IU of vitamin D3 daily is expected to raise blood levels of 25(OD)D by 10 ng/ml after a few weeks. But it may take months to resolve symptoms of severe vitamin D deficiency such as rickets in children. It depends on how low your vitamin D levels were in the first place and some individual factors. Obesity, polluted environments, and malabsorption syndromes (such as Crohn’s disease) are just some factors that can increase the time it takes for vitamin D levels to work. Continue reading

You can raise your vitamin D levels quickly in three main ways, but it can take up to a week for increased vitamin D intake or exposure to be reflected in a vitamin D blood test: increasing your intake of foods that are naturally rich in vitamin D or fortified with vitamin D, taking a vitamin D supplement, or getting outside and exposing your skin to sunlight (although experts do not recommend this without sun protection). Continue reading

Experts cannot say if oral vitamin D helps improve psoriasis symptoms, because overall, trial results have been mixed. While some open-label studies show a moderate to marked improvement (with some reports of remission), most double-blinded RCTs have shown only slight or no improvement. Supplementation could be considered on a case-by-case basis. Continue reading

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Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.