Mequinol is a drug

Drug

A drug, broadly speaking, is any substance that, when absorbed into the body of a living organism, alters normal bodily function. There is no single, precise definition, as there are different meanings in drug control law, government regulations, medicine, and colloquial usage.In pharmacology, a...

 used in combination with the drug tretinoin

Tretinoin

Tretinoin is the acid form of vitamin A and is also known as all-trans retinoic acid or ATRA. It is a drug commonly used to treat acne vulgaris and keratosis pilaris. It is available as a cream or gel...

 in the treatment of liver spots

Liver spots

Liver spots are blemishes on the skin associated with aging and exposure to ultraviolet radiation from the sun...

. Mequinol used alone and in higher doses is used as a topical

Topical

In medicine, a topical medication is applied to body surfaces such as the skin or mucous membranes such as the vagina, anus, throat, eyes and ears.Many topical medications are epicutaneous, meaning that they are applied directly to the skin...

 drug

Drug

A drug, broadly speaking, is any substance that, when absorbed into the body of a living organism, alters normal bodily function. There is no single, precise definition, as there are different meanings in drug control law, government regulations, medicine, and colloquial usage.In pharmacology, a...

 for medical depigmentation

Depigmentation

Depigmentation is the lightening of the skin, or loss of pigment. Depigmentation of the skin can be caused by a number of local and systemic conditions. The pigment loss can be partial or complete...

.

Chemistry

It is the monomethyl ether

Ether

Ethers are a class of organic compounds that contain an ether group — an oxygen atom connected to two alkyl or aryl groups — of general formula R–O–R'. A typical example is the solvent and anesthetic diethyl ether, commonly referred to simply as "ether"...

 of hydroquinone

Hydroquinone

Hydroquinone, also benzene-1,4-diol or quinol, is an aromatic organic compound that is a type of phenol, having the chemical formula C6H42. Its chemical structure, shown in the table at right, has two hydroxyl groups bonded to a benzene ring in a para position. It is a white granular solid...

, and an isomer

Isomer

In chemistry, isomers are compounds with the same molecular formula but different structural formulas. Isomers do not necessarily share similar properties, unless they also have the same functional groups. There are many different classes of isomers, like stereoisomers, enantiomers, geometrical...

 of guaiacol

Guaiacol

Guaiacol is a naturally occurring organic compound with the formula C6H4. Although it is biosynthesized by a variety of organisms, this colorless aromatic oil is usually derived from guaiacum or wood creosote. Samples darken upon exposure to air and light. Guaiacol is present in wood smoke,...

.

It is often used to inhibit polymerization in monomers that polymerize with radical mechanisms, such as acrylates, methacrylates or styrene.

Uses

A combination of mequinol 2% (depigmentation agent) & tretinoin

Tretinoin

Tretinoin is the acid form of vitamin A and is also known as all-trans retinoic acid or ATRA. It is a drug commonly used to treat acne vulgaris and keratosis pilaris. It is available as a cream or gel...

 0.01% (topical

Topical

In medicine, a topical medication is applied to body surfaces such as the skin or mucous membranes such as the vagina, anus, throat, eyes and ears.Many topical medications are epicutaneous, meaning that they are applied directly to the skin...

 retinoid

Retinoid

The retinoids are a class of chemical compounds that are related chemically to vitamin A. Retinoids are used in medicine, primarily due to the way they regulate epithelial cell growth....

) is commonly used in treating solar lentigines (liver spots

Liver spots

Liver spots are blemishes on the skin associated with aging and exposure to ultraviolet radiation from the sun...

 & age spots). Exactly how it works is unknown, but this compound is used along with a total skin care and sunlight avoidance program. This compound may also be used for other conditions as determined by one's dermatologist. Methoxyphenol is a depigmentation

Depigmentation

Depigmentation is the lightening of the skin, or loss of pigment. Depigmentation of the skin can be caused by a number of local and systemic conditions. The pigment loss can be partial or complete...

 agent, like Monobenzone

Monobenzone

Monobenzone is a compound used as a topical drug for medical depigmentation.-Chemistry:Monobenzone is the monobenzyl ether of hydroquinone. Monobenzone occurs as a white, almost tasteless crystalline powder, soluble in alcohol and practically insoluble in water.-Pharmacology:The topical application...

 (benzyloxyphenol), it is the active ingredient

Active ingredient

An active ingredient is the substance of a pharmaceutical drug or a pharmaceutical ingredient and bulk active in medicine; in pesticide formulations active substance may be used. Some medications and pesticide products may contain more than one active ingredient...

 in some depigmenting creams and ointments. A formulation of 20% 4-methoxyphenol ointment causes depigmentation

Depigmentation

Depigmentation is the lightening of the skin, or loss of pigment. Depigmentation of the skin can be caused by a number of local and systemic conditions. The pigment loss can be partial or complete...

 in animal tissue.

Lower dosages of topical mequinol and the Q-switched Ruby Laser have been used to depigment normal skin in vitiligo

Vitiligo

Vitiligo is a condition that causes depigmentation of sections of skin. It occurs when melanocytes, the cells responsible for skin pigmentation, die or are unable to function. The cause of vitiligo is unknown, but research suggests that it may arise from autoimmune, genetic, oxidative stress,...

patients with disseminated (greater than 50 percent of body surface area) idiopathic vitiligo.