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Vitamin A supplements are used to increase vitamin A levels. These products may contain vitamin A or provitamin A, which is a substance that the body turns into vitamin A. The most common form of provitamin A is beta-carotene. Before taking vitamin A, 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. Taking too much vitamin A can be dangerous. Talk to your health care provider if you are unsure whether you need to take a vitamin A supplement.

Uses

What are vitamin A supplements used for?

Vitamin A supplements are commonly taken to increase vitamin A levels. The benefits of vitamin A supplements for other uses are not well defined.

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

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

Vitamin A supplements provide vitamin A, also known as retinol. Your body needs vitamin A to maintain normal vision and keep your heart, lungs, and immune system working well. In children, vitamin A is important for growth.

There are two forms of vitamin A.

  • Preformed vitamin A, which is usually called vitamin A. This form is found in fish, animal liver, dairy, and eggs. 
  • Provitamin A, which the body turns into vitamin A. This form is found in vegetables and fruits, especially red, orange, and yellow ones. The most common form of provitamin A is beta-carotene. 

In the United States, most people get enough vitamin A from their diet. For most adults, the recommended daily intake of vitamin A is 700-900 micrograms (mcg). However, some people either do not get enough from their diet or have trouble absorbing it. When this happens, you can take vitamin A supplements to replace what you are not getting from your diet.

How are vitamin A supplements supplied (dosage forms)?

Vitamin A supplements are available as a dietary supplement in various strengths and dosage forms to supplement levels of this vitamin.

How should I store vitamin A supplements?

You should store vitamin A supplements according to the product label. Most medicines should be kept in a cool, dry place that is out of the reach of children and pets and not in direct sunlight.

Side Effects

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

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

There may be other side effects of vitamin A supplements that are not listed here. 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 A supplements?

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

Severe Allergic Reactions. Vitamin A supplements may cause allergic reactions, which can be serious. Stop taking vitamin A 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 A supplements?

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

  • Beta-carotene
  • Retinyl acetate
  • Retinyl palmitate
  • Vitamin A
  • Any of the ingredients in the specific product dispensed

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

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

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

Vitamin A supplements are dietary supplements. They cannot be marketed to treat or cure a disease.

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

Keep vitamin A supplements out of the reach of children.

If you are using a liquid vitamin A supplement, use an accurate measuring device to measure your dose. 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 A from several places, including foods and other vitamins or supplements. Many multivitamins and combination supplement products have vitamin A in them. It is important not to take too much vitamin A. Too much preformed vitamin A can be harmful (hypervitaminosis A). Provitamin A, such as beta-carotene, is not harmful when taken in large amounts. If you are not sure whether you should take vitamin A or beta-carotene, or how much you need, talk to your health care provider. 

Vitamin A is measured in a unit known as retinol activity equivalents (RAE). This is because your body absorbs preformed vitamin A differently than provitamin A (such as beta-carotene). The recommended daily intake of vitamin A for most adults is 700-900 mcg RAE. This is the same as 1400-1800 mcg of beta-carotene from supplements.

What should I tell my health care provider before using vitamin A 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 A 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 A 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 food you eat. Talk to your health care provider about taking a vitamin A supplement and checking your blood levels of this vitamin.

Other Medicines and Supplements. Vitamin A supplements may interact with other medicines and supplements. Before taking vitamin A 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. Too much vitamin A may cause harm to a fetus. 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 A supplements while you are pregnant or trying to get pregnant.

Breastfeeding. Vitamin A 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 vitamin A supplements while breastfeeding.

Interactions

Do vitamin A supplements interact with foods or drinks?

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

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

Do vitamin A 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 vitamin A supplements.

  • Acitretin (Soriatane), which is a medicine used to treat psoriasis
  • Bexarotene (Targretin), which is a medicine for a certain form of cancer
  • Orlistat (Alli, Xenical), which is a medicine used for weight loss

This may not be a complete list of medicines that can interact with vitamin A 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 A supplement?

If you or someone else has used too many vitamin A supplements, 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 vitamin A supplements?

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.