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Vitamin D supplements are taken to increase your vitamin D levels. Before taking a vitamin D supplement, talk to your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. Vitamin D is found in many over-the-counter (OTC) products. Too much vitamin D can be dangerous. Your health care provider can measure your blood levels to see if you may need to take a vitamin D supplement. 

Uses

What are vitamin D supplements used for?

Vitamin D supplements are commonly taken to increase vitamin D levels. 

Vitamin D supplements may also be used for other conditions as determined by your health care provider.

How do vitamin D supplements work (mechanism of action)?

Vitamin D supplements increase the amount of vitamin D in your body. Vitamin D helps your body absorb calcium from foods and supplements. It also helps your body maintain normal phosphate levels. 

How are vitamin D supplements supplied (dosage forms)?

Brands and other names

  • Amerix Vitamin D3
  • Cholecalciferol 
  • Decara
  • Ergocalciferol
  • Pediatric D-Vite

Dosage forms and strengths

Vitamin D supplements are available as cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2). These are available as dietary supplements in various strengths and dosage forms. 

Ergocalciferol is also available as a prescription for other uses. See Ergocalciferol (Drisdol).

How should I store vitamin D supplements?

Vitamin D supplements should be stored at room temperature, usually between about 68 F and 77 F (20 C and 25 C). Storage requirements may vary slightly among products. Follow the storage instructions for the product you are taking. If you are unsure how to store it, ask your pharmacist. 

Side Effects

What are the most common side effects of vitamin D supplements?

Vitamin D supplements are usually well tolerated. Tell your health care provider if you have any side effects that bother you.

Contact your health care provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088 (800-332-1088). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of vitamin D supplements?

While less common, the most serious side effects of vitamin D supplements are described below, along with what to do if they happen.

Severe Allergic Reactions. Vitamin D supplements may cause allergic reactions, which can be serious. Stop taking vitamin D supplements and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching or skin rash
  • Bumps on the skin called hives that can be red, pink, white, or brown depending on your skin tone
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Warnings & Precautions

Who should not use vitamin D supplements?

Allergies to Ingredients. People who are allergic to any of the following should not take vitamin D supplements.

  • Amerix Vitamin D3
  • Cholecalciferol
  • Decara
  • Ergocalciferol
  • Pediatric D-Vite
  • Any other vitamin D supplement
  • Any of the ingredients in the specific product

Your pharmacist can tell you all of the ingredients in the specific vitamin D supplement products they stock.

High Calcium Levels. You should not take vitamin D supplements if you have high calcium levels. Vitamin D helps your body absorb calcium. Taking vitamin D when you have high calcium levels could make your calcium levels too high. 

Vitamin D Toxicity. You should not take vitamin D supplements if your vitamin D levels are too high, also known as hypervitaminosis D. Your health care provider can order a blood test to check your vitamin D level.

What should I know about vitamin D supplements before using one?

Read and follow the directions on the specific product you are taking or take it as recommended by your health care provider. 

Keep vitamin D supplements out of the reach of children.

If you are using a liquid vitamin D supplement, shake it well before each use. Use an accurate measuring device to measure your dose of liquid vitamin D supplements. A household spoon is not an accurate measuring device and may cause you to take the wrong dose. Ask your pharmacist what measuring device to use.

You get vitamin D from several places, including the sun, foods, and other vitamins or supplements. Many multivitamins and combination supplement products have vitamin D in them. It is important not to take too much vitamin D. Too much vitamin D can be harmful (hypervitaminosis D). If you are not sure how much vitamin D you need or if you need a vitamin D supplement, talk to your health care provider. 

What should I tell my health care provider before using vitamin D supplements ?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know if vitamin D supplements are right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions. Tell your health care provider if you have any of the following.

Malabsorption Syndrome. You may have trouble absorbing vitamin D supplements if you have malabsorption syndrome. Malabsorption means your body is not able to absorb and use the nutrients that you take by mouth or from the foods you eat. Talk with your health care provider about taking a vitamin D supplement and checking your blood levels of this vitamin.

Other Medicines and Supplements. Vitamin D supplements may interact with other medicines and supplements. Before taking vitamin D supplements, tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. Tell your health care provider if you are pregnant or plan to become pregnant. Your health care provider will let you know if you should take vitamin D supplements while you are pregnant or trying to get pregnant.

Breastfeeding. Vitamin D supplements pass into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed. Your health care provider will let you know if you should take a vitamin D supplement while breastfeeding.

Interactions

Do vitamin D supplements interact with foods or drinks?

You should take vitamin D supplements with food or a meal that has fat in it. Vitamin D is a fat-soluble vitamin. Taking it with fat helps your body to absorb it. 

It is unknown if drinking alcohol will affect vitamin D supplements.

Do vitamin D supplements interact with other medicines (drug interactions)?

Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using any of the following before taking a vitamin D supplement.

  • A statin, such as atorvastatin (Lipitor and others) or rosuvastatin (Crestor), which is a medicine to lower cholesterol
  • Orlistat (Alli, Xenical), which is a medicine used for weight loss
  • A thiazide diuretic, such as hydrochlorothiazide, chlorthalidone, or indapamide, which is a medicine commonly used to lower blood pressure

This may not be a complete list of medicines that can interact with vitamin D supplements. Always check with your health care provider.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much of a vitamin D supplement?

If you or someone else has taken too much of a vitamin D supplement, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of a vitamin D supplement?

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.