Health Guide
Drug Guide

Vitamin A (Oral route, intramuscular route)

Pronunciation:

VYE-ta-min A

Brand Names:

Dosage Forms:

Classifications:

Therapeutic

Nutritive Agent

Pharmacologic

Vitamin A (class)

Uses of This Medicine:

Vitamins are compounds that you must have for growth and health. They are needed in small amounts only and are usually available in the foods that you eat. Vitamin A is needed for night vision and for growth of skin, bones, and male and female reproductive organs. In pregnant women vitamin A is necessary for the growth of a healthy fetus.

Lack of vitamin A may lead to a rare condition called night blindness (problems seeing in the dark), as well as dry eyes, eye infections, skin problems, and slowed growth. Your health care professional may treat these problems by prescribing vitamin A for you.

Some conditions may increase your need for vitamin A. These include:

In addition, infants receiving unfortified formula may need vitamin A supplements.

Vitamin A absorption will be decreased in any condition in which fat is poorly absorbed.

Increased need for vitamin A should be determined by your health care professional.

Claims that vitamin A is effective for treatment of conditions such as acne or lung diseases, or for treatment of eye problems, wounds, or dry or wrinkled skin not caused by lack of vitamin A have not been proven. Although vitamin A is being used to prevent certain types of cancer, some experts feel there is not enough information to show that this is effective, particularly in well-nourished individuals.

Injectable vitamin A is given by or under the supervision of a health care professional. Other forms of vitamin A are available without a prescription.

For good health, it is important that you eat a balanced and varied diet. Follow carefully any diet program your health care professional may recommend. For your specific dietary vitamin and/or mineral needs, ask your health care professional for a list of appropriate foods. If you think that you are not getting enough vitamins and/or minerals in your diet, you may choose to take a dietary supplement.

Vitamin A is found in various foods including yellow-orange fruits and vegetables; dark green, leafy vegetables; vitamin A-fortified milk; liver; and margarine. Vitamin A comes in two different forms, retinols and beta-carotene. Retinols are found in foods that come from animals (meat, milk, eggs). The form of vitamin A found in plants is called beta-carotene (which is converted to vitamin A in the body). Food processing may destroy some of the vitamins. For example, freezing may reduce the amount of vitamin A in foods.

Vitamins alone will not take the place of a good diet and will not provide energy. Your body needs other substances found in food, such as protein, minerals, carbohydrates, and fat. Vitamins themselves often cannot work without the presence of other foods. For example, small amounts of fat are needed so that vitamin A can be absorbed into the body.

The daily amount of vitamin A needed is defined in several different ways.

Age or ConditionForm of Vitamin A
RE or mcg of RetinolAmount in Units as RetinolAmount in Units as a Combination of Retinol and Beta-carotene
Infants and children
Birth to 3 years
375–4001250–13301875–2000
4 to 6 years50016652500
7 to 10 years70023303500
Teenage and adult males100033305000
Teenage and adult females80026654000
Pregnant females80026654000
Breast-feeding females1200–13004000–43306000–6500

Note: Based on 1980 U.S. Recommended Dietary Allowances (RDAs) for vitamin A in the diet that is a combination of retinol and beta-carotene.

Age or ConditionForm of Vitamin A
RE or mcg of RetinolAmount in Units as RetinolAmount in Units as a Combination of Retinol and Beta-carotene
Infants and children
Birth to 3 years
40013302000
4 to 6 years50016652330
7 to 10 years700–8002330–26653500
Teenage and adult males100033305000
Teenage and adult females80026654000
Pregnant females9002665–30004000–4500
Breast-feeding females120040006000

Note: Based on 1980 U.S. Recommended Dietary Allowances (RDAs) for vitamin A in the diet that is a combination of retinol and beta-carotene.

In the past, the RDA and RNI for vitamin A have been expressed in Units. This term Units has been replaced by retinol equivalents (RE) or micrograms (mcg) of retinol, with 1 RE equal to 1 mcg of retinol. This was done to better describe the two forms of vitamin A, retinol and beta-carotene. One RE of vitamin A is equal to 3.33 Units of retinol and 10 Units of beta-carotene. Some products available have not changed their labels and continue to be labeled in Units.

Before Using This Medicine:

If you are taking this dietary supplement without a prescription, carefully read and follow any precautions on the label. For this supplement, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Children

Problems in children have not been reported with intake of normal daily recommended amounts. However, side effects from high doses and/or prolonged use of vitamin A are more likely to occur in young children than adults.

Older adults

Problems in older adults have not been reported with intake of normal daily recommended amounts. However, some studies have shown that the elderly may be at risk of high blood levels of vitamin A with long-term use.

Pregnancy

Pregnancy CategoryExplanation
All TrimestersXStudies in animals or pregnant women have demonstrated positive evidence of fetal abnormalities. This drug should not be used in women who are or may become pregnant because the risk clearly outweighs any possible benefit.

Breast-feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Other medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are receiving this dietary supplement, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this dietary supplement with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Other interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other medical problems

The presence of other medical problems may affect the use of this dietary supplement. Make sure you tell your doctor if you have any other medical problems, especially:

Proper Use of This Medicine:

If you miss taking a vitamin for one or more days there is no cause for concern, since it takes some time for your body to become seriously low in vitamins. However, if your health care professional has recommended that you take this vitamin, try to remember to take it as directed every day.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

For individuals taking the oral liquid form of vitamin A:

Missed dose

If you miss a dose of this medicine, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Precautions While Using This Medicine:

Vitamin A is stored in the body; therefore, when you take more than the body needs, it will build up in the body. This may lead to poisoning and even death. Problems are more likely to occur in:

Remember that the total amount of vitamin A you get every day includes what you get from foods that you eat and what you take as a supplement.

High doses and/or prolonged use of vitamin A may cause bleeding from the gums; dry or sore mouth; or drying, cracking, or peeling of the lips.

Side Effects of This Medicine:

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Bleeding from gums or sore mouth
bulging soft spot on head (in babies)
confusion or unusual excitement
diarrhea
dizziness or drowsiness
double vision
headache (severe)
irritability (severe)
peeling of skin, especially on lips and palms
vomiting (severe)

Check with your doctor as soon as possible if any of the following side effects occur:

Bone or joint pain
convulsions (seizures)
drying or cracking of skin or lips
dry mouth
fever
general feeling of discomfort or illness or weakness
headache
increased sensitivity of skin to sunlight
increase in frequency of urination, especially at night, or in amount of urine
irritability
loss of appetite
loss of hair
stomach pain
unusual tiredness
vomiting
yellow-orange patches on soles of feet, palms of hands, or skin around nose and lips

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.


Last Updated: 10/12/2016

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