Selenium

Selenium is found in multivitamins and other dietary supplements in different forms, including sodium selenate and selenomethionine. Selenium is an “essential mineral” as it is not produced by the body. Obtained from the diet, it helps maintain proper immune system and thyroid function (thyroid hormone synthesis), by activating certain selenium-dependent proteins (selenoproteins) and enzymes, such as glutathione peroxidase, which is an antioxidant. Adequate intake of selenium is required to reduce oxidative stress and the production of free radicals.

High-selenium food sources include Brazil nuts, seafood, meats, grains, dairy products, and eggs, which have variable selenium content. Most people have a daily intake of selenium of about 100 mcg, which is sufficient for normal thyroid and immune function. Levels above 400 mcg of combined dietary and supplemental selenium can lead to selenium toxicity.

More information on the recommended dietary allowance and sources of selenium can be found at the National Institutes of Health, Office of Dietary Supplements Fact Sheet.

Follow all directions given to you by your doctor and read all documents provided, including the full Prescribing Information, FDA-Approved Product Labeling, Instructions for Use, and Medication Guide, before using Selenium. However, the following is a synopsis of the general guidelines for the use of Selenium:

• Do not take selenium supplements unless you have been instructed by a doctor to do so.
• The recommended dietary allowance of selenium changes with age.
• Selenium use can affect the results of certain medical tests, and even surgery, by increasing your risk of bleeding. Tell every doctor who treats you that you are using selenium.

The most common side effects of Selenium seen in clinical trials as compared to placebo include:

• Garlic-smelling breath.
• Nail or hair loss.
• Brittle hair or nails.
• Change in teeth color.
• Fatigue.
• Irritability.
• Skin Rashes.
• Nausea, diarrhea.

Some individuals may experience serious side effects while using Selenium at high doses for long periods of time. These side effects may require immediate medical attention. If you experience any of the following, contact your healthcare provider or seek emergency medical help:

• Selenosis, which can affect the liver, skin, nails, and hair.
• Selenium toxicity, seen when daily intake exceeds 400 mcg/day, may present as severe headaches, gastrointestinal symptoms (nausea, vomiting), liver dysfunction, kidney failure, and muscle spasms.

These are not all of the possible side effects of Selenium. You should always seek medical advice from your healthcare provider for any questions or concerns about your medical condition or treatment. Read all patient information, medication guides, or drug information sheets that come with this medication. You can also report adverse effects to the Food and Drug Administration at www.fda.gov/medwatch or 1-800-FDA-1088.

Chronic intake of selenium past the upper limit of the recommended dietary allowance (200 mcg for several years) may also put you at a higher risk of chronic conditions such as:

Type 2 diabetes

Amyotrophic lateral sclerosis (ALS)

Before starting Selenium, it is crucial to discuss any existing health conditions with your healthcare provider. You should be sure that your healthcare provider is aware of all your medical conditions, including whether you have:

• A family history of type 2 diabetes, or are pre-diabetic.
• Chronic kidney disease.
• Underactive thyroid.
• Skin cancer.
• Autoimmune diseases such as multiple sclerosis, systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA).

You have a normal amount of selenium in the blood.

Allergy or hypersensitivity to selenium.

The onset of the effectiveness of selenium depends on the condition being treated, the degree of selenium deficiency, and the amount of selenium being ingested. In general, selenium levels should return to normal within one month of initiating selenium supplements.

When Selenium is taken with other prescription drugs, over-the-counter medications, vitamins, and supplements, it may change how they work or increase the frequency or severity of side effects. Make sure that you tell your healthcare professional about anything that you are taking to avoid any negative drug interactions, including:

• Anticoagulant or antiplatelet drugs such as warfarin, aspirin, clopidogrel, and sedative drugs such as barbiturates. These medications may have a more potent effect when used in combination with selenium supplements.
• Simvastatin may be less effective when used in combination with selenium supplements.

• Capsules (100 mcg to 200 mcg)
• Tablets (50 mcg to 200 mcg)
• Oral liquid

Selenium supplements should be stored in a cool, dry place away from children or pets.

Selenium is available over the counter from mineral supplement manufacturers such as Jamieson, Nature’s Bounty, and Webber Naturals.

Yes, it is sold by most manufacturers of mineral supplements.

Selenium supplements can be discontinued under the supervision of a doctor, and do not need to be tapered.

Talk to your doctor if you are already pregnant or if you have any plans to become pregnant. They will know or recommend what is best for you.

When used in recommended doses under the direction of a physician, selenium is considered safe in pregnancy.

Talk to your doctor if you are already breastfeeding or if you have any plans to breastfeed. They will know or recommend what is best for you. When used in recommended doses under the direction of a physician, selenium is considered safe when lactating.