Selenium disulfide, also known as selenium sulfide, is a chemical compound and medication used to treat pityriasis versicolor, seborrhoeic dermatitis, and dandruff.[3] It is applied to the affected area as a lotion or shampoo.[4] Dandruff frequently returns if treatment is stopped.[5]
Side effects include hair loss, irritation of the skin, weakness, and feeling tired.[3] Use is not recommended in children less than 2–5 years old.[3][5] Use in pregnancy or breastfeeding has not been studied.[6] Selenium disulfide is an inorganic compound with the chemical formula SeS2.[7]
Selenium disulfide is sold as an antifungal agent in shampoos for the treatment of dandruff and seborrheic dermatitis associated in the scalp with fungi of genus Malassezia.[10][11][12] In the United States, a 1% strength is available over-the-counter, and a 2.5% strength is also available with a prescription. In Canada, the 2.5% strength is available over-the-counter. At the 2.5% strength, selenium disulfide is also used on the body to treat Tinea versicolor, a type of fungal skin infection caused by a different species of Malassezia. It has been suggested to be effective as a treatment for hyperkeratosis.[13]
Structure of 1,2,3-Se3S5, illustrative of selenium sulfide.
Selenium disulfide has a composition that approximates to SeS2 and is sometimes called selenium sulfide. However, as used in proprietary formulations, it is not a pure chemical compound but a mixture where the overall Se:S ratio is 1:2. The compounds are Se–S rings containing a variable number of S and Se atoms, SenS8−n.[14]
Many selenium sulfides are known as indicated by 77Se-NMR spectroscopy.[15]
Selenium monosulfide, along with elemental selenium and sulfur, has been used in medicinal preparations in the past,[16] causing confusion and contradiction[17] as to exactly what form selenium is in any given topical preparation.
In the film Evolution selenium was mentioned as an active ingredient of Head & Shoulders. A group of academics, therefore, tried to use this brand of shampoo to stop an alien invasion after discovering that the alien life form was sensitive to selenium. In fact, the modern shampoo from this brand no longer contains selenium sulfide and instead zinc pyrithione is used as a dandruff-reducing component.[18]
↑Gupta, Aditya K.; Mays, Rachel R.; Folley, Kelly A. (2019). "42. Topical antifungal agents". In Wolverton, Stephen E.; Wu, Jashin J. (eds.). Comprehensive Dermatologic Drug Therapy (4th ed.). Elsevier. p. 488. ISBN978-0-323-61211-1. Archived from the original on 2021-10-09. Retrieved 2021-10-07.
↑ 4.04.14.2Hamilton, Richart (2015). Tarascon Pocket Pharmacopoeia 2015 Deluxe Lab-Coat Edition. Jones & Bartlett Learning. p. 194. ISBN9781284057560.
↑ 5.05.15.2"Selenium Sulfide". The American Society of Health-System Pharmacists. Archived from the original on 18 January 2017. Retrieved 8 January 2017.
↑World Health Organization (2019). World Health Organization model list of essential medicines: 21st list 2019. Geneva: World Health Organization. hdl:10665/325771. WHO/MVP/EMP/IAU/2019.06. License: CC BY-NC-SA 3.0 IGO.
↑British national formulary : BNF 69 (69 ed.). British Medical Association. 2015. p. 829. ISBN9780857111562.
↑Cyclic selenium sulfides R. Steudel, R. Laitinen, Topics in Current Chemistry, (1982), 102, 177-197
↑Pekonen, Pentti.; Hiltunen, Yrjō; Laitinen, Risto S.; Pakkanen, Tapani A. (1991). "Chalcogen ring interconversion pathways. 77Se NMR spectroscopic study of the decomposition of 1,2,3,4,5-Se5S2 to 1,2,3,4,5,6-Se6S2 and 1,2,3,4-Se4S2". Inorganic Chemistry. 30 (19): 3679. doi:10.1021/ic00019a022.
Grover, R. W. (1956). "Diffuse Hair Loss Associated with Selenium (Selsun) Sulfide Shampoo". JAMA: The Journal of the American Medical Association. 160 (16): 1397. doi:10.1001/jama.1956.02960510023006.
Givens, T. G.; Murray, M. M.; Baker, R. C. (1995). "Comparison of 1% and 2.5% Selenium Sulfide in the Treatment of Tinea Capitis". Archives of Pediatrics and Adolescent Medicine. 149 (7): 808–11. doi:10.1001/archpedi.1995.02170200098016. PMID7795774.
Ransone, James W.; Scott, Norman M.; Knoblock, Edward C. (1961). "Selenium Sulfide Intoxication". New England Journal of Medicine. 264 (8): 384. doi:10.1056/NEJM196102232640806. PMID13739506.
Laitinen, Risto S.; Pakkanen, Tapani A. (1987). "77Se NMR spectroscopic characterization of selenium sulfide ring molecules SenS8−n". Inorganic Chemistry. 26 (16): 2598. doi:10.1021/ic00263a010.