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Other drug names: A-Am An-Az B C-Ch Ci-Cz D-Dh Di-Dz E F G H I-J K-L M-Mh Mi-Mz N-Nh Ni-Nz O P-Pl Pm-Pz Q-R S-Sn So-Sz T-To Tp-Tz U-V W-Z 0-9   

Selenium Supplements (Systemic)

Brand Names

Some commonly used brand names are:

In the U.S.-


For quick reference, the following selenium supplements are numbered to match the corresponding brand names.
This information applies to the following:
1.  Selenious Acid (se-LEE-nee-us as-id) ** ****�
2.  Selenium (se-LEE-nee-um) **
**  Generic name product may be available in the U.S.
***  Generic name product may be available in Canada
*  Not commercially available in the U.S.
****�  Not commercially available in Canada


  • Nutritional supplement, mineral  --Selenious Acid; Selenium


Selenium supplements are used to prevent or treat selenium deficiency.

The body needs selenium for normal growth and health. Selenium is needed for certain enzymes that help with normal body functions.

Lack of selenium may lead to changes in fingernails, muscle weakness, and heart problems.

Selenium deficiency in the United States is rare. Patients receiving total parenteral nutrition (TPN) for long periods of time may need selenium. Selenium deficiency is a problem in areas of the world where the soil contains little selenium.

Although selenium is being used to prevent certain types of cancer, there is not enough information to show that this is effective.

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

Selenium supplements are available as part of a multivitamin/mineral complex or alone in the following dosage forms:

  • Selenium
    • Tablets (U.S. and Canada)
  • Selenious Acid
    • Injection (U.S.)

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.Selenium is found in seafood, liver, lean red meat, and grains grown in soil that is rich in selenium.

The daily amount of selenium 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).
    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 for selenium are generally defined as follows:

  • Infants and children-
    • Birth to 3 years of age: 10 to 20 micrograms (mcg) per day.
    • 4 to 6 years of age: 20 mcg per day.
    • 7 to 10 years of age: 30 mcg per day.
  • Adolescent and adult males-40 to 70 mcg per day.
  • Adolescent and adult females-45 to 55 mcg per day.
  • Pregnant females-65 mcg per day.
  • Breast-feeding females-75 mcg per day.

Before Using This Medicine

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

Allergies- Tell your health care professional if you have ever had any unusual or allergic reaction to selenious acid or selenium. 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 and minerals when you become pregnant and that you continue to receive the right amount of vitamins and minerals throughout your pregnancy. The healthy growth and development of the fetus depend on a steady supply of nutrients from the mother. However, taking large amounts of a dietary supplement in pregnancy may be harmful to the mother and/or fetus and should be avoided.

Studies in animals have shown that selenium causes birth defects when given in large doses.

Breast-feeding- It is important that you receive the right amounts of vitamins and minerals so that your baby will also get the vitamins and minerals 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.

Older adults- Problems in older adults have not been reported with intake of normal daily recommended amounts.

Other medicines- Medicines or dietary supplements

Although certain medicines should not be used together at all, in other cases medicines or dietary supplements 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. Tell your health care professional if you are taking any other dietary supplement or any nonprescription (over-the-counter [OTC]) or prescription medicine.

Other medical problems- The presence of other medical problems may affect the use of selenium supplements. Make sure you tell your health care professional if you have any other medical problems, especially:
  • Kidney problems or
  • Stomach problems-These conditions may cause higher blood levels of selenium, which may increase the chance of unwanted effects

Proper Use of This Medicine


The amount of selenium needed to meet normal daily recommended intakes will be different for different patients. The following information includes only the average amounts of selenium.

  • For oral dosage form (tablets):
    • To prevent deficiency, the amount taken by mouth is based on normal daily recommended intakes:
      • Adult and teenage males-40 to 70 micrograms (mcg) per day.
      • Adult and teenage females-45 to 55 mcg per day.
      • Pregnant females-65 mcg per day.
      • Breast-feeding females-75 mcg per day.
      • Children 7 to 10 years of age-30 mcg per day.
      • Children 4 to 6 years of age-20 mcg per day.
      • Children birth to 3 years of age-10 to 20 mcg per day.
    • To treat deficiency:
      • Adults, teenagers, and children-Treatment dose is determined by prescriber for each individual based on severity of deficiency.

Missed dose-

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


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 dietary supplement from freezing. Do not refrigerate.
  • Do not keep outdated dietary supplement or those no longer needed. Be sure that any discarded dietary supplement is out of the reach of children.

Side Effects of This Medicine

Side Effects of This Dietary Supplement

Along with its needed effects, a dietary supplement may cause some unwanted effects. Although selenium supplements have not been reported to cause any side effects, check with your health care professional immediately if any of the following side effects occur as a result of an overdose:

  • Symptoms of overdose
    • Diarrhea;  fingernail weakening;  garlic odor of breath and sweat;  hair loss;  irritability;  itching of skin;  metallic taste;  nausea and vomiting;  unusual tiredness and weakness  

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