Monobenzone

Monobenzone
Systematic (IUPAC) name
4-(benzyloxy)phenol
Clinical data
AHFS/Drugs.com International Drug Names
  • CA: Unscheduled
  • US: Rx-only, Unscheduled
Topical
Identifiers
103-16-2 Yes
D11AX13
PubChem CID 7638
DrugBank DB00600 Yes
ChemSpider 7356 
UNII 9L2KA76MG5 
KEGG D05072 Yes
ChEMBL CHEMBL1388 
Synonyms Hydroquinone benzyl ether, Hydroquinone monobenzyl ether, Benzyl p-hydroxyphenyl ether, Benzyl hydroquinone, Benzoquin, 4-(phenylmethoxy)phenol
Chemical data
Formula C13H12O2
200.233180 g/mol
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4-(Benzyloxy)phenol, or Monobenzone, is an organic chemical in the phenol family with chemical formula C6H5CH2OC6H4OH.[1][2] It is used as a topical drug for medical depigmentation.[3][4] It is a colourless solid that is classified as the monobenzyl ether of hydroquinone. Monobenzone is soluble in alcohol, benzene, and diethyl ether, and practically insoluble in water.

Pharmacology

The topical application of monobenzone in animals increases the excretion of melanin from melanocytes. The same action is thought to be responsible for the depigmenting effect of the drug in humans. Monobenzone may cause destruction of melanocytes and permanent depigmentation.

The histology of the skin after depigmentation with topical monobenzone is the same as that seen in vitiligo; the epidermis is normal except for the absence of identifiable melanocytes. Therefore, monobenzone is used as a topical medicine to permanently depigment normal skin surrounding vitiliginous lesions only in patients with disseminated (greater than 50 percent of body surface area) idiopathic vitiligo.Monobenzone is also being considered for the treatment of Melanoma.[5]

Vitiligo

Vitiligo is a chronic skin disease that causes loss of melanocytes which are pigment-producing cells, resulting in irregular pale or white patches of skin. The cellular and molecular mechanisms leading to the destruction of melanocytes in this disorder have not yet been detected. Vitiligo affects approximately 0.5 to 1 percent of the population. Individuals of all ethnic origins and both sexes can be affected; however, it is much more noticeable on darker skin. Common areas of the skin losing pigment are the face, lips, hands, arms, legs, and genital areas. Patches of the epidermis affected by vitiligo often occur symmetrically across both sides on the body. Seldom, small areas of the body may repigment as they are recolonised by melanocytes.

There is no known cure for the disease but treatments do exist. Some patients use cosmetic make-up to cover the white spots, while others use treatments such as repigmentation through a series of ultraviolet light treatments and surgical transplant of melanocytes. In severe cases, when over fifty percent of the body surface area is covered with white patches, patients cannot use these repigmentation treatments. They can, however, choose to eliminate the skin colour from the normal areas using monobenzone cream,[6] a process called depigmentation. This gives the patient’s skin a permanent, even, pale white colour. Since the application of monobenzone is topical, it can be done in the privacy of one’s home. It is simple to do and does not require frequent visits to a doctor’s office. Twice daily monobenzone topical cream must be applied.

The major side effect of depigmentation therapy is inflammation (redness and swelling) of the skin. Patients may experience itching or dry skin. The process of depigmentation is gradual. The length of time using monobenzone topical cream ranges from four months to a year. The patient must understand the concept of continued existence of a source of follicular melanocytes and that exposure to the sun can lead to perifollicular pigmented macules. Rigorous limitation of sun exposure is essential following depigmentation therapy, not only to avoid burns, but to avoid perifollicular repigmentation. Wearing high-SPF sunscreens is the ultimate physical barrier to help avoid burns and repigmentation.

There are at least three theories about the principal cause of vitiligo:

Other uses

Monobenzone is also used to derive dyes for fiber dyeing and is used in the rubber industry.

References

Further reading