Selenium sulfide
Selenium disulfide is an inorganic compound
Inorganic compound
Inorganic compounds have traditionally been considered to be of inanimate, non-biological origin. In contrast, organic compounds have an explicit biological origin. However, over the past century, the classification of inorganic vs organic compounds has become less important to scientists,...

 with the approximate formula SeS2. Both sulfur and selenium catenate (form chains and rings) readily, and mixtures of selenium and sulfur likewise give rise to numerous "alloys". This compound is not an analogue of sulfur dioxide
Sulfur dioxide
Sulfur dioxide is the chemical compound with the formula . It is released by volcanoes and in various industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide unless the sulfur compounds are removed before burning the fuel...


Medicinal selenium disulfide

The material commercially called selenium disulfide is sold as an antifungal agent in shampoo
Shampoo is a hair care product used for the removal of oils, dirt, skin particles, dandruff, environmental pollutants and other contaminant particles that gradually build up in hair...

s for the treatment of dandruff
Dandruff is the shedding of dead skin cells from the scalp . Dandruff is sometimes caused by frequent exposure to extreme heat and cold. As it is normal for skin cells to die and flake off, a small amount of flaking is normal and common; about 487,000 cells/cm2 get released normally after...

 and seborrheic dermatitis associated in the scalp with Malassezia genus fungi. In the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

, a 1% strength is available over-the-counter
Over-the-counter drug
Over-the-counter drugs are medicines that may be sold directly to a consumer without a prescription from a healthcare professional, as compared to prescription drugs, which may be sold only to consumers possessing a valid prescription...

, and a 2.5% strength is also available with a prescription
Medical prescription
A prescription is a health-care program implemented by a physician or other medical practitioner in the form of instructions that govern the plan of care for an individual patient. Prescriptions may include orders to be performed by a patient, caretaker, nurse, pharmacist or other therapist....

. At the 2.5% strength, selenium disulfide is also used on the body to treat tinea versicolor
Tinea versicolor
Tinea versicolor is a condition characterized by a rash on the trunk and proximal extremities. Recent research has shown that the majority of Tinea versicolor is caused by the Malassezia globosa fungus, although Malassezia furfur is responsible for a small number of cases...

, a type of fungal skin infection caused by a different species of Malassezia.

Chemical composition

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 is a mixture where the overall Se:S ratio is 1:2. The compounds are cyclic Se–S rings containing a variable number of S and Se atoms, SenS8n. Selenium disulfide can cause discoloration of the hair
Hair is a filamentous biomaterial, that grows from follicles found in the dermis. Found exclusively in mammals, hair is one of the defining characteristics of the mammalian class....

 and alter the color of hair dyes. It may also discolor metal
A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...

lic jewellery
Jewellery or jewelry is a form of personal adornment, such as brooches, rings, necklaces, earrings, and bracelets.With some exceptions, such as medical alert bracelets or military dog tags, jewellery normally differs from other items of personal adornment in that it has no other purpose than to...


Other selenium sulfides

Many selenium sulfides are known. A useful means for characterization is 77Se NMR spectroscopy. Chalcogen ring interconversion pathways. Selenium monosulfide (SeS) is the only selenium compound so far identified as a carcinogen
A carcinogen is any substance, radionuclide, or radiation that is an agent directly involved in causing cancer. This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes...

 in animal
Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...

s. Selenium monosulfide, along with elemental selenium and sulfur, has been used in medicinal preparations in the past, causing confusion and contradiction as to exactly what form selenium is in in any given topical preparation.

See also

  • Zinc pyrithione
    Zinc pyrithione
    Zinc pyrithione is a coordination complex of zinc. This colourless solid is used as an antifungal and antibacterial agent. This coordination complex, which has many names, was first reported in the 1930s.- Structure of the compound :...

    , an antimicrobial agent used in some medicated shampoos.
  • Selsun Blue
    Selsun Blue
    Selsun Blue is an over-the-counter brand of dandruff shampoo now owned by Sanofi-Aventis. First made by Abbott Laboratories, the brand was bought in Chattem in 2002. Chattem was acquired by Sanofi-Aventis in 2010. Selsun Blue has been marketed as a more effective alternative to brand leader Head &...

    , a shampoo with selenium disulfide as its active ingredient.
  • Ketoconazole
    Ketoconazole is a synthetic antifungal drug used to prevent and treat fungal skin infections, especially in immunocompromised patients such as those with AIDS or those on chemotherapy. Ketoconazole is sold commercially as an anti-dandruff shampoo, topical cream, and oral tablet.Ketoconazole is...

    , another antifungal agent used in shampoos.
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