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Vitamin A (Systemic)

Brand Names

In the U.S.-

  • Aquasol A

In Canada-

  • Aquasol A

Another commonly used name is retinol.

Category

  • Nutritional supplement, vitamin

Description

Vitamins (VYE-ta-mins) 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:

  • Diarrhea
  • Eye diseases
  • Intestine diseases
  • Infections (continuing or chronic)
  • Measles
  • Pancreas disease
  • Stomach removal
  • Stress (continuing)

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.

Vitamin A is available in the following dosage forms:

    Oral
  • Capsules (U.S. and Canada)
  • Oral drops (Canada)
  • Oral solution (U.S. and Canada)
  • Tablets (U.S.)
    Parenteral
  • Injection (U.S. and Canada)


Importance of Diet

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.

    For U.S.-
  • Recommended Dietary Allowances (RDAs) are the amount of vitamins and minerals needed to provide for adequate nutrition in most healthy persons. RDAs for a given nutrient may vary depending on a person's age, sex, and physical condition (e.g., pregnancy).
  • Daily Values (DVs) are used on food and dietary supplement labels to indicate the percent of the recommended daily amount of each nutrient that a serving provides. DV replaces the previous designation of United States Recommended Daily Allowances (USRDAs).
  • Normal daily recommended intakes in the United States for vitamin A are generally defined according to age or condition and to the form of vitamin A as follows: Age or Condition Form of Vitamin A RE or mcg of Retinol Amount in Units as Retinol Amount in Units as a Combination of Retinol and Beta-carotene Infants and children Birth to 3 years 375****�01250****�30 1875****�00 4 to 6 years 50016652500 7 to 10 years700 23303500Teenage and adult males1000 33305000Teenage and adult females80026654000 Pregnant females 80026654000Breast-feeding females1200****�004000****�30 6000****�00

    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.

    For Canada-
  • Recommended Nutrient Intakes (RNIs) are used to determine the amounts of vitamins, minerals, and protein needed to provide adequate nutrition and lessen the risk of chronic disease.
  • Normal daily recommended intakes in Canada for vitamin A are generally defined according to age or condition and to the form of vitamin A as follows: Age or ConditionForm of Vitamin ARE or mcg of RetinolAmount in Units as RetinolAmount in Units as a Combination of Retinol and Beta-carotene Infants and children Birth to 3 years40013302000 4 to 6 years500 16652500 7 to 10 years 700****�02330****�65 3500Teenage and adult males100033305000 Teenage and adult females 80026654000Pregnant females9002665****�00 4000****�00 Breast-feeding females 120040006000

    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 vitamin A, the following should be considered:

Allergies- Tell your health care professional if you have ever had any unusual or allergic reaction to vitamin A. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy- It is especially important that you are receiving enough vitamins when you become pregnant and that you continue to receive the right amount of vitamins throughout your pregnancy. The healthy growth and development of the fetus depend on a steady supply of nutrients from the mother.

However, taking too much vitamin A (more than 1800 RE [6000 Units]) during pregnancy can also cause harmful effects such as birth defects or slow or reduced growth in the child.

Breast-feeding- It is especially important that you receive the right amounts of vitamins so that your baby will also get the vitamins needed to grow properly. However, taking large amounts of a dietary supplement while breast-feeding may be harmful to the mother and/or baby and should be avoided.

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.

Dental

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.

Other medicines- Medicines or other dietary supplements

Although certain medicines or dietary supplements should not be used together at all, in other cases they may be used together even if an interaction might occur. In these cases, your health care professional may want to change the dose, or other precautions may be necessary. When you are taking vitamin A, it is especially important that your health care professional know if you are taking any of the following:

  • Etretinate or
  • Isotretinoin (e.g., Accutane)-Use with vitamin A may cause high blood levels of vitamin A, which may increase the chance of side effects

Other medical problems- The presence of other medical problems may affect the use of vitamin A. Make sure you tell your health care professional if you have any other medical problems, especially:
  • Alcohol abuse (or history of) or
  • Liver disease-Vitamin A use may make liver problems worse
  • Kidney disease-May cause high blood levels of vitamin A, which may increase the chance of side effects


Proper Use of This Medicine

Dosing-

The amount of vitamin A needed to meet normal daily recommended intakes will be different for different individuals. The following information includes only the average amounts of vitamin A. The combination of retinol and beta-carotene in the diet is based on 1980 U.S. Recommended Dietary Allowances (RDAs).

  • For oral dosage form (capsules, tablets, oral solution):
    • To prevent deficiency, the amount taken by mouth is based on normal daily recommended intakes:
        For the U.S.
      • Adult and teenage males-1000 retinol equivalents (RE) (3330 Units of retinol or 5000 Units as a combination of retinol and beta-carotene) per day.
      • Adult and teenage females-800 RE (2665 Units of retinol or 4000 Units as a combination of retinol and beta-carotene) per day.
      • Pregnant females-800 RE (2665 Units of retinol or 4000 Units as a combination of retinol and beta-carotene) per day.
      • Breast-feeding females-1200 to 1300 RE (4000 to 4330 Units of retinol or 6000 to 6500 Units as a combination of retinol and beta-carotene) per day.
      • Children 7 to 10 years of age-700 RE (2330 Units of retinol or 3500 Units as a combination of retinol and beta-carotene) per day.
      • Children 4 to 6 years of age-500 RE (1665 Units of retinol or 2500 Units as a combination of retinol and beta-carotene) per day.
      • Children birth to 3 years of age-375 to 400 RE (1250 to 1330 Units of retinol or 1875 to 2000 Units as a combination of retinol and beta-carotene) per day.
        For Canada
      • Adult and teenage males-1000 RE (3330 Units of retinol or 5000 Units as a combination of retinol and beta-carotene) per day.
      • Adult and teenage females-800 RE (2665 Units of retinol or 4000 Units as a combination of retinol and beta-carotene) per day.
      • Pregnant females-900 RE (2665 to 3000 Units of retinol or 4000 to 4500 Units as a combination of retinol and beta-carotene) per day.
      • Breast-feeding females-1200 RE (4000 Units of retinol or 6000 Units as a combination of retinol and beta-carotene) per day.
      • Children 7 to 10 years of age-700 to 800 RE (2330 to 2665 Units of retinol or 3500 Units as a combination of retinol and beta-carotene) per day.
      • Children 4 to 6 years of age-500 RE (1665 Units of retinol or 2500 Units as a combination of retinol and beta-carotene) per day.
      • Children birth to 3 years of age-400 RE (1330 Units or 2000 Units as a combination of retinol and beta-carotene) per day.
    • To treat deficiency:
      • Adults and teenagers-Treatment dose is determined by prescriber for each individual based on severity of deficiency. The following dose has been determined for xerophthalmia (eye disease): Oral, 7500 to 15,000 RE (25,000 to 50,000 Units) a day.
      • Children-Treatment dose is determined by prescriber for each individual based of severity of deficiency. The following doses have been determined:
        • For measles-
          • Children 6 months to 1 year of age: Oral, 30,000 RE (100,000 Units) as a single dose.
          • For children 1 year of age and older: Oral, 60,000 RE (200,000 Units) as a single dose.
        • Xerophthalmia (eye disease)-
          • Children 6 months to 1 year of age: Oral, 30,000 RE (100,000 Units) as a single dose, the same dose being repeated the next day and again at 4 weeks.
          • Children 1 year of age and older: Oral, 60,000 RE (200,000 Units) as a single dose, the same dose being repeated the next day and again at 4 weeks.

          Note:

          Vitamin A is used in measles and xerophthalmia only when vitamin A deficiency is a problem as determined by your health care professional. Vitamin A deficiency occurs in malnutrition or in certain disease states.

Missed dose-

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.

For individuals taking the oral liquid form of vitamin A:

  • This preparation is to be taken by mouth even though it comes in a dropper bottle.
  • This dietary supplement may be dropped directly into the mouth or mixed with cereal, fruit juice, or other food.

Storage-

To store this dietary supplement:

  • Keep out of the reach of children.
  • Store away from heat and direct light.
  • Do not store in the bathroom, near the kitchen sink or in other damp places. Heat or moisture may cause the dietary supplement to break down.
  • Keep the oral liquid form of this dietary supplement from freezing.
  • Do not keep outdated dietary supplements or those no longer needed. Be sure that any discarded dietary supplement is out of the reach of children.


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:

  • Adults taking 7500 RE (25,000 Units) a day for 8 months in a row, or 450,000 RE (1,500,000 Units) all at once; or
  • Children taking 5400 RE (18,000 Units) to 15,000 RE (50,000 Units) a day for several months in a row, or 22,500 RE (75,000 Units) to 105,100 RE (350,000 Units) all at once.
  • Pregnant women taking more than 1800 RE (6000 Units) a day.

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.


Side Effects of This Medicine

Side Effects of This Dietary Supplement

Along with its needed effects, a dietary supplement may cause some unwanted effects. Vitamin A does not usually cause any side effects at normal recommended doses.

However, taking large amounts of vitamin A over a period of time may cause some unwanted effects that can be serious. Check with your health care professional immediately if any of the following side effects occur, since they may be signs of sudden overdose:

  • 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 health care professional as soon as possible if any of the following side effects occur, since they may also be signs of gradual overdose:

  • 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 above may also occur in some individuals. If you notice any other effects, check with your health care professional.



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Last updated: Tue, 06 Jan 2009 00:20:03 GMT
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