Products
Selenium is commercially available as a drug and as a dietary supplement and is included in various multivitamin preparations. As a monopreparation, it is available in the form of tablets, as a drinking solution, and as an injection preparation (e.g., Burgerstein Selenvital, Selenase), among others.
Structure and properties
Selenium (Se, Mr = 78.96 g/mol) is present in products including sodium selenite pentahydrate (Na2SeO3 – 5H2O) or contained in the form of organic molecules such as selenomethionine. Selenium forms both organic and inorganic compounds and is similar to sulfur, which is directly above it in the periodic table.
Effects
Selenium (ATC A12CE02) has antioxidant properties. It is an essential trace element found, among other things, in the proteinogenic amino acid selenocysteine, which is integrated into the so-called selenoproteins (e.g., selenoprotein P) and selenoenzymes. These enzymes include glutathione peroxidase and iodothyronine deiodinase, which is involved in the conversion of the thyroid hormone T4 to T3. Glutathione peroxidase is a component of the antioxidant protection system. Selenomethionine can replace the amino acid methionine in proteins. The amount of selenium in the body is in the milligram range. The roles of selenium in the body include protection against oxidative stress and cancer, as well as normal functioning of the immune system and thyroid gland.
Indications
- For the treatment of proven selenium deficiency.
- For food supplementation, in multivitamin preparations (supplementation).
Dosage
According to the professional information. Dosages are in the microgram range. Selenium should not be overdosed. Long-term high-dose supplementation is apparently not recommended (see Rayman et al, 2018).
Contraindications
- Hypersensitivity
- Selenium intoxication
Full precautions can be found in the drug label.
Adverse effects
Possible adverse effects include allergic reactions. Acute overdose manifests as a garlicky breath odor, fatigue, nausea, diarrhea, and abdominal pain. Chronic overdose results in nail and hair growth disorders and peripheral polyneuropathies.
