Actions of Selenium in details
Selenium is a trace element that is essential in small amounts in the body. Selenium is important in the functioning of Selenium dependent chemical (enzymes) in the body called as selanoproteins. Selenium is an integral part of glutathione peroxidases (GPx) that act as potent antioxidant (substance that protects against cell damage) by neutralizing the free radicals (waste products formed in the body during energy production) such as reactive oxygen and nitrogen species. Thus Selenium participates in vital redox reactions of the body. Also, a selenoprotein (iodothyronine deiodinases) is essential for the conversion of thyroxine (T4) to the biologically active thyroid hormone triiodothyronine (T3) thereby indicating the importance of Selenium in thyroid hormone functioning.
How should I take Selenium?
If you are using the 2.5% strength of Selenium: Use Selenium only as directed. Do not use it more often than recommended on the label, unless otherwise directed by your doctor.
If you are using the 1% strength of Selenium : For best results, use Selenium at least 2 times a week or as directed by your doctor.
To use Selenium for dandruff or seborrheic dermatitis of the scalp:
- Before using Selenium, wet the hair and scalp with lukewarm water.
- Apply enough medicine (1 or 2 teaspoonfuls) to the scalp to work up a lather. Allow the lather to remain on the scalp for 2 to 3 minutes, then rinse.
- Apply the medicine again and rinse well.
- If Selenium is used on light or blond, gray, or chemically treated (bleached, tinted, permanent-waved) hair, rinse your hair well for at least 5 minutes after using the medicine to lessen the chance of hair discoloration.
- After treatment, wash your hands well.
To use Selenium for tinea versicolor of the body:
- Apply the medicine to the affected areas of your body, except for your face and genitals (sex organs).
- Work up a lather using a small amount of water.
- Allow the medicine to remain on your skin for 10 minutes.
- Rinse your body well to remove all the medicine.
Do not use Selenium if blistered, raw, or oozing areas are present on your scalp or the area of your body that is to be treated, unless otherwise directed by your doctor.
Keep Selenium away from the eyes. If you should accidentally get some in your eyes, flush them thoroughly with water.
Dosing
The dose of Selenium 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 Selenium. 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 lotion dosage form:
- For dandruff or seborrheic dermatitis:
- Adults and children—If you are using the 1% lotion, use on the scalp two times a week. If you are using the 2.5% lotion, use on the scalp two times a week for two weeks, then use one time a week or less often.
- Infants—Use and dose must be determined by your doctor.
- For tinea versicolor:
- Adults and children—Use the 2.5% lotion on the body one time a day for seven days.
- Infants—Use and dose must be determined by your doctor.
- For dandruff or seborrheic dermatitis:
Missed Dose
If you miss a dose of Selenium, take it as soon as possible. However, if it is almost time for your next dose, 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.
Selenium administration
Oral: Bariatric surgery: Tablet, extended release: Some institutions may have specific protocols that conflict with these recommendations; refer to institutional protocols as appropriate. ER tablets should be swallowed whole. Do not break, crush, or chew. IR tablet, capsule, oral solution, and injectable formulations are available. If safety and efficacy can be effectively monitored, no change in formulation or administration is required after bariatric surgery. Bariatric vitamin supplementation is recommended on a lifelong basis after surgery; may consider integration of daily Selenium regimen into the bariatric vitamin regimen.
Selenium pharmacology
Selenium is part of glutathione peroxidase which protects cell components from oxidative damage due to peroxides produced in cellular metabolism.
Prolonged TPN support in humans has resulted in Selenium deficiency symptoms which include muscle pain and tenderness. The symptoms have been reported to respond to supplementation of TPN solutions with Selenium.
Pediatric conditions, Keshan disease, and Kwashiorkor, have been associated with low dietary intake of Selenium. The conditions are endemic to geographical areas with low Selenium soil content. Dietary supplementation with Selenium salts has been reported to reduce the incidence of the conditions among affected children.
Normal blood levels of Selenium in different human populations have been found to vary and depend on the Selenium content of the food consumed. Results of surveys carried out in some countries are tabulated below:
| COUNTRY | Number of Samples | Selenium (mcg/100 mL) (a) | ||
| Whole Blood | Blood Cells | Plasma/ Serum | ||
| (a) Mean values with or without standard deviation in parentheses, all other ranges. | ||||
| (b) Age group unknown. | ||||
| (c) Three children recovered from Kwashiorkor and the other six under treatment for other diseases. | ||||
| (d) Low Selenium-content soil area. | ||||
| (e) Well nourished children, three recovered from Kwashiorkor and the other six under treatment for other diseases. | ||||
| (f) Mean values from seven subjects. | ||||
| Canada | 254 Adults | (37.9 ± 7.8) | (23.6 ± 6.0) | (14.4 ± 2.9) |
| England | 8 (b) | 26-37 (32) | —— | —— |
| Guatemala & Southern USA | 10 Adults 9 Children (c) | 19-28 (22) (23 ± 5) | —— (36 ± 12) | —— (15 ± 5) |
| New Zealand (d) | 113 Adults | (5.4 ± 0.1) | (6.6 ± 0.3) | (4.3 ± 0.1) |
| Thailand | 3 Adults 9 Children (e) | 14.4-20.2 (12.0 ± 3.6) (f) | 17.8-35.8 (19.5 ± 8.2) | 8.1-12.5 (8.3 ± 2.2) |
| USA | 210 Adults | 15.7-25.6 (20.6) | —— | —— |
Plasma Selenium levels of 0.3 and 0.9 mcg/100 mL have been reported to produce deficiency symptoms in humans.
Selenium is eliminated primarily in urine. However, significant endogenous losses through feces also occur. The rate of excretion and the relative importance of two routes varies with the chemical form of Selenium used in supplementation. Ancillary routes of elimination are lungs and skin.
References
- NCIt. "Selenium: NCI Thesaurus (NCIt) provides reference terminology for many systems. It covers vocabulary for clinical care, translational and basic research, and public information and administrative activities.". https://ncit.nci.nih.gov/ncitbrowser... (accessed September 17, 2018).
- EPA Air Toxics. "Selenium compounds: EPA Health Effects Notebook for Hazardous Air Pollutants". https://www.epa.gov/sites/production... (accessed September 17, 2018).
- EPA Chemicals under the TSCA. "Selenium: The Chemical Data Reporting under the Toxic Substances Control Act (TSCA) contains chemical physical description and chemical use categories.". http://www.epa.gov/chemical-data-rep... (accessed September 17, 2018).
Reviews
The results of a survey conducted on ndrugs.com for Selenium are given in detail below. The results of the survey conducted are based on the impressions and views of the website users and consumers taking Selenium. We implore you to kindly base your medical condition or therapeutic choices on the result or test conducted by a physician or licensed medical practitioners.User reports
Consumer reported administration
No survey data has been collected yetConsumer reviews
There are no reviews yet. Be the first to write one! |
Information checked by Dr. Sachin Kumar, MD Pharmacology
