Selenium disulfide

Last updated
Selenium disulfide
Clinical data
Trade names Selseb, Selsun Blue, others
Other namesSelenium sulfide
AHFS/Drugs.com Monograph
MedlinePlus a682258
Routes of
administration 		Topical
ATC code
Legal status
Legal status
Identifiers
CAS Number
PubChem CID
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
ECHA InfoCard 100.028.458 OOjs UI icon edit-ltr-progressive.svg
Chemical and physical data
Formula S2Se
Molar mass 143.09 g·mol−1
3D model (JSmol)
Density 3 g/cm3
Melting point 111 °C (232 °F)
Boiling point 118 to 119 °C (244 to 246 °F) (decomposes)
Solubility in water negligible mg/mL (20 °C)
  • S=[Se]=S
  • InChI=1S/S2Se/c1-3-2
  • Key:JNMWHTHYDQTDQZ-UHFFFAOYSA-N

Selenium disulfide, also known as selenium sulfide, is a chemical compound and medication used to treat seborrheic dermatitis, dandruff, and pityriasis versicolor. [1] [2] It is applied to the affected area as a lotion or shampoo. [3] Symptoms frequently return if treatment is stopped. [4]

Contents

Side effects may include hair discoloration, skin irritation, and risk of systemic absorption and toxicity, among others. [1] Use is not recommended in children less than 2–5 years old. [1] [4] Use in pregnancy or breastfeeding has not been studied. [5] It consists of a mixture of inorganic covalent compounds having an approximate empirical formulas of SeS2. [6] Selenium disulfide acts as a keratolytic and antifungal agent. [7] [8] [9]

Selenium disulfide was approved for medical use in the United States at least as early as 1951. [4] It is on the World Health Organization's List of Essential Medicines. [10] Selenium disulfide is available as a generic medication and over the counter. [3]

Medical uses

Selenium disulfide is sold as an antifungal agent in shampoos (such as Selsun Blue) for the treatment of dandruff and seborrheic dermatitis associated in the scalp with fungi of genus Malassezia . [11] [12] [13] It is also used on the body to treat tinea versicolor (pityriasis versicolor), a type of fungal skin infection caused by a different species of Malassezia. [2] [14]

A 2015 systematic review of topical treatments for seborrheic dermatitis of the scalp identified only a single randomized controlled trial evaluating selenium disulfide for the condition. [15] It was a three-arm trial of 246 people with moderate to severe dandruff and compared treatment with 2% ketoconazole shampoo (n=97), 2.5% selenium disulfide shampoo (n=100), and placebo (shampoo base with no antiseborrheic agent) (n=49) for 29 days. [15] [16] The study found a 73% reduction in dandruff score with ketoconazole, a 67% reduction with selenium disulfide, and a 45% reduction with placebo. [15] [16] Based on the study, the systematic review concluded that selenium disulfide may be effective in the treatment of dandruff but that the available evidence is limited and overall evidence quality is low. [15] It also found that while selenium disulfide has infrequent side effects, it seems to have more side effects than ketoconazole shampoo. [15] Consequently, the review concluded that selenium disulfide should not be considered as a first-line therapy but instead should be used as an alternative treatment after other therapies like ketoconazole shampoo have proven not effective. [15]

A 2015 review recommended topical antifungal agents, topical corticosteroids, and topical calcineurin inhibitors like tacrolimus as the main treatments for seborrheic dermatitis based on good-quality evidence, rather than selenium disulfide for which evidence is much more limited. [17] However, the review did suggest use of over-the-counter selenium disulfide shampoos as an inexpensive option for managing mild symptoms of seborrheic dermatitis. [17]

Available forms

Selenium disulfide is available in the form of a prescription drug as a 2.25% medical shampoo. [18] [19] In the United States, a 1% strength is available over-the-counter, and a 2.5% strength is also available with a prescription. [19] In Canada, the 2.5% strength is available over-the-counter. [19] Selsun Blue is an over-the-counter shampoo for dandruff with 1% selenium disulfide as its active ingredient. [20] [19]

Side effects

Side effects of selenium disulfide shampoo for dandruff appear to be infrequent. [15] [16] A randomized controlled trial of 100 people who received selenium disulfide reported side effects of itching or burning sensation of the scalp (3 people), eruption near the hairline (1 person), psoriasis (1 person), lightening or bleaching of hair color (2 people), orange staining of the scalp (1 person), and a chemical taste while shampooing (1 person). [15] [16]

Selenium disulfide can cause discoloration of nails and light hair [7] and can alter the color of hair dyes. Several scattered case reports of orange to red–brown scalp discoloration with selenium sulfide shampoo exist. [7] [21] The discoloration resolved shortly following discontinuation of selenium disulfide shampoo and its removal could be facilitated by lightly swabbing with isopropyl alcohol. [21] Selenium disulfide may also discolor metallic jewellery. Case reports of temporary diffuse hair loss with selenium disulfide shampoo exist as well. [22] [23] Excessive environmental or occupational exposure to selenium has also been associated with hair loss and other adverse effects. [22] However, hair loss has not been reported with topical selenium disulfide in several large studies. [21]

Selenium disulfide should not be applied to damaged skin as there is a risk of systemic absorption and associated toxicity. [1] Systemic symptoms may include tremors, weakness, lethargy, lower abdominal pain, and occasional vomiting. [1] These symptoms usually resolve within 10 days following exposure. [1]

Pharmacology

Pharmacodynamics

Selenium disulfide acts as an antifungal and keratolytic agent to treat seborrheic dermatitis and dandruff. [7] [8] [9]

Pharmacokinetics

The systemic absorption and toxicity of orally administered selenium sulfide has been studied in animals. [24] [7] Topical use of selenium sulfide in the form of a shampoo or lotion in humans does not appear to normally increase circulating or urinary selenium levels. [25] [26] [27] [28] [29] However, application of selenium disulfide to damaged skin can result in systemic absorption and has been associated with cases of toxicity. [1] Selenium disulfide appears to be much less toxic than other selenium salts, which may be attributed to its low aqueous solubility and very poor systemic absorption. [7]

Chemistry

Composition

Structure of 1,2,3-Se3S5, illustrative of selenium sulfide 1,2,3-Se3S5.svg
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 of eight-membered-ring compounds where the overall Se:S ratio is 1:2. The specific chemicals contain a variable number of S and Se atoms, SenS8−n. [30]

Many selenium sulfides are known, as indicated by 77Se-NMR spectroscopy. [31]

History

Selenium sulfide was introduced for medical use in the United States in 1951. [4] [19]

Selenium monosulfide, along with elemental selenium and sulfur, has been used in medicinal preparations in the past, [32] causing confusion and contradiction [33] as to exactly what form selenium is in any given topical preparation.

Society and culture

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. [34]

Research

Selenium disulfide has been suggested to be effective as a treatment for hyperkeratosis based on a small case series of three treated patients. [35] It has also been reported to be effective in the treatment of scalp psoriasis based on clinical observation of over 100 treated patients and two case reports of dramatic response. [36]

Selenium sulfide is under development for the treatment of meibomianitis (meibomian gland dysfunction) and dry eyes in topical and ophthalmic formulations. [37] [38] [19] As of March 2021, it is in phase 2/3 clinical trials for meibomianitis and phase 2 trials for dry eyes. [37] The developmental code name of selenium sulfide for these uses is AZR-MD-001 and it is being developed by Azura Ophthalmics. [37]

Related Research Articles

<span class="mw-page-title-main">Dandruff</span> Skin condition of the scalp

Dandruff is a skin condition that mainly affects the scalp. Symptoms include flaking and sometimes mild itchiness. It can result in social or self-esteem problems. A more severe form of the condition, which includes inflammation of the skin, is known as seborrhoeic dermatitis.

<span class="mw-page-title-main">Tinea versicolor</span> Skin disease

Tinea versicolor is a condition characterized by a skin eruption on the trunk and proximal extremities. The majority of tinea versicolor is caused by the fungus Malassezia globosa, although Malassezia furfur is responsible for a small number of cases. These yeasts are normally found on the human skin and become troublesome only under certain conditions, such as a warm and humid environment, although the exact conditions that cause initiation of the disease process are poorly understood.

<span class="mw-page-title-main">Seborrhoeic dermatitis</span> Skin disease

Seborrhoeic dermatitis is a long-term skin disorder. Symptoms include flaky, scaly, greasy, and occasionally itchy and inflamed skin. Areas of the skin rich in oil-producing glands are often affected including the scalp, face, and chest. It can result in social or self-esteem problems. In babies, when the scalp is primarily involved, it is called cradle cap. Seborrhoeic dermatitis of the scalp may be described in lay terms as dandruff due to the dry, flaky character of the skin. However, as dandruff may refer to any dryness or scaling of the scalp, not all dandruff is seborrhoeic dermatitis. Seborrhoeic dermatitis is sometimes inaccurately referred to as seborrhoea.

<span class="mw-page-title-main">Zinc pyrithione</span> Chemical compound

Zinc pyrithione is a coordination complex of zinc. It has fungistatic and bacteriostatic properties and is used in the treatment of seborrhoeic dermatitis and dandruff.

<span class="mw-page-title-main">Ketoconazole</span> Antifungal chemical compound

Ketoconazole, sold under the brand name Nizoral among others, is an antiandrogen, antifungal, and antiglucocorticoid medication used to treat a number of fungal infections. Applied to the skin it is used for fungal skin infections such as tinea, cutaneous candidiasis, pityriasis versicolor, dandruff, and seborrheic dermatitis. Taken by mouth it is a less preferred option and only recommended for severe infections when other agents cannot be used. Other uses include treatment of excessive male-patterned hair growth in women and Cushing's syndrome.

<span class="mw-page-title-main">Tinea capitis</span> Cutaneous fungal infection of the scalp

Tinea capitis is a cutaneous fungal infection (dermatophytosis) of the scalp. The disease is primarily caused by dermatophytes in the genera Trichophyton and Microsporum that invade the hair shaft. The clinical presentation is typically single or multiple patches of hair loss, sometimes with a 'black dot' pattern, that may be accompanied by inflammation, scaling, pustules, and itching. Uncommon in adults, tinea capitis is predominantly seen in pre-pubertal children, more often boys than girls.

<span class="mw-page-title-main">Ciclopirox</span> Antifungal medication

Ciclopirox is a synthetic antifungal agent for topical dermatologic treatment of superficial mycoses. It is most useful against tinea versicolor. It is often used clinically as ciclopirox olamine, the olamine salt of ciclopirox.

The management of hair loss, includes prevention and treatment of alopecia, baldness, and hair thinning, and regrowth of hair.

<span class="mw-page-title-main">Cradle cap</span> Human medical condition

Cradle cap causes crusty or oily scaly patches on a baby's scalp. The condition is not painful or itchy, but it can cause thick white or yellow scales that are not easy to remove. Cradle cap most commonly begins sometime in the first three months but can occur in later years. Similar symptoms in older children are more likely to be dandruff than cradle cap. The rash is often prominent around the ear, the eyebrows or the eyelids. It may appear in other locations as well, where it is called infantile seborrhoeic dermatitis. Cradle cap is just a special—and more benign—case of this condition. The exact cause of cradle cap is not known. Cradle cap is not spread from person to person (contagious). It is also not caused by poor hygiene. It is not an allergy, and it is not dangerous. Cradle cap often lasts a few months. In some children, the condition can last until age 2 or 3.

<span class="mw-page-title-main">Dermatophytosis</span> Fungal infection of the skin

Dermatophytosis, also known as ringworm, is a fungal infection of the skin (Dermatomycosis). Typically it results in a red, itchy, scaly, circular rash. Hair loss may occur in the area affected. Symptoms begin four to fourteen days after exposure. Multiple areas can be affected at a given time.

Selsun Blue is an over-the-counter brand of dandruff shampoo now owned by Sanofi. First made by Abbott Laboratories, the brand was bought by Chattem in 2002. Chattem was acquired by Sanofi in 2010, although in some markets, it is sold by Rohto Pharmaceutical instead. Selsun Blue has been marketed as a more effective alternative to brand leader Head & Shoulders due to its superior performance in randomized trials.

<i>Malassezia furfur</i> Species of fungus

Malassezia furfur is a species of yeast that is naturally found on the skin surfaces of humans and some other mammals. It is associated with a variety of dermatological conditions caused by fungal infections, notably seborrhoeic dermatitis and tinea versicolor. As an opportunistic pathogen, it has further been associated with dandruff, malassezia folliculitis, pityriasis versicolor (alba), and malassezia intertrigo, as well as catheter-related fungemia and pneumonia in patients receiving hematopoietic transplants.

<span class="mw-page-title-main">Tinea nigra</span> Medical condition

Tinea nigra, also known as superficial phaeohyphomycosis and Tinea nigra palmaris et plantaris, is a superficial fungal infection, a type of phaeohyphomycosis rather than a tinea, that causes usually a single 1–5 cm dark brown-black, non-scaly, flat, painless patch on the palms of the hands and the soles of the feet of healthy people. There may be multiple spots. The macules occasionally extend to the fingers, toes, and nails, and may be reported on the chest, neck, or genital area. Tinea nigra infections can present with multiple macules that can be mottled or velvety in appearance, and may be oval or irregular in shape. The macules can be anywhere from a few mm to several cm in size.

<i>Microsporum audouinii</i> Species of fungus

Microsporum audouinii is an anthropophilic fungus in the genus Microsporum. It is a type of dermatophyte that colonizes keratinized tissues causing infection. The fungus is characterized by its spindle-shaped macroconidia, clavate microconidia as well as its pitted or spiny external walls.

<span class="mw-page-title-main">Pityriasis amiantacea</span> Medical condition

Pityriasis amiantacea is an eczematous condition of the scalp in which thick tenaciously adherent scale infiltrates and surrounds the base of a group of scalp hairs. It does not result in scarring or alopecia.

<span class="mw-page-title-main">Climbazole</span> Chemical compound

Climbazole is a topical antifungal agent commonly used in the treatment of human fungal skin infections such as dandruff, seborrhoeic dermatitis and eczema. Climbazole has shown a high in vitro and in vivo efficacy against Malassezia spp. that appear to play an important role in the pathogenesis of dandruff. Its chemical structure and properties are similar to other azole fungicides such as ketoconazole, clotrimazole and miconazole.

Anti-seborrheics are drugs effective in seborrheic dermatitis. Selenium sulfide, zinc pyrithione, corticosteroids, imidazole antifungals, and salicylic acid are common anti-seborrheics.

<span class="mw-page-title-main">Pyrithione</span> Chemical compound

Pyrithione is the common name of an organosulfur compound with molecular formula C
5H
5NOS, chosen as an abbreviation of pyridinethione, and found in the Persian shallot. It exists as a pair of tautomers, the major form being the thione 1-hydroxy-2(1H)-pyridinethione and the minor form being the thiol 2-mercaptopyridine N-oxide; it crystallises in the thione form. It is usually prepared from either 2-bromopyridine, 2-chloropyridine, or 2-chloropyridine N-oxide, and is commercially available as both the neutral compound and its sodium salt. It is used to prepare zinc pyrithione, which is used primarily to treat dandruff and seborrhoeic dermatitis in medicated shampoos, though is also an anti-fouling agent in paints.

Topical antifungaldrugs are used to treat fungal infections on the skin, scalp, nails, vagina or inside the mouth. These medications come as creams, gels, lotions, ointments, powders, shampoos, tinctures and sprays. Most antifungal drugs induce fungal cell death by destroying the cell wall of the fungus. These drugs inhibit the production of ergosterol, which is a fundamental component of the fungal cell membrane and wall.

References

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