Melasma

Key Points
Skin condition typically affecting the face, particularly the cheeks, upper lip and forehead
Caused by overproduction of melanin by pigment cells
Consists of blotchy patches of brownish color, forming and then fading gradually

Melasma is a skin condition which typically affects the face, in particular the cheeks, upper lip and forehead, though it may spread to affect the neck. It consists of blotchy patches which are brownish in color. Blotches appear gradually and then slowly fade over time. The condition is typically divided into three subtypes based on the part of the skin they affect. Epidermal melasma affects the surface of the skin, and blotches are dark brown in color with a well-demarcated border. Epidermal melasma may appear more prominent under a blacklight. Dermal melasma affects the deeper layers of skin, resulting in light brown, poorly defined blotches which remain unchanged in appearance under a blacklight. Mixed melasma is a combination of dermal and epidermal Melasma, and affected persons will develop both types of blotches. This is the most common form of melasma.

Melasma is caused by the overproduction of melanin by pigment producing cells. The exact cause for this is unknown, but it is thought that affected persons may be genetically predisposed to its development. Certain triggers such as hormonal changes, sun exposure, pregnancy, phototoxic reactions to scented soaps or cosmetics may spark the condition. However, some cases may develop independently of any triggers. The condition most commonly affects women, although men may rarely develop it.

Differential Diagnosis (Other conditions with similar appearance)
Addison Disease
Drug-induced Photosensitivity
Lupus erythematosus, Discoid
Mastocytosis
Poikiloderma of Civatte

Diagnosis
Key Points
Diagnosis based on appearance of the affected area
Further testing is typically not required

Melasma is generally diagnosed based on the appearance of the affected area. Further testing is typically not required.

Treatment
Effectiveness of treatment is predicated on condition subtype
Goal of treatment is control and reduction of symptoms
Successfully treated pigmentation may reappear if exposed to triggers

Treatment of melasma and its effectiveness is often predicated on what subtype of the condition is extant. Epidermal melasma responds well to therapy, while dermal Melasma does not. Treatment of mixed melasma may only be partially effective, due to the nature of the subtype. The goal of treatment in all forms of the condition is the control and reduction of symptoms. It is recommended that affected persons discontinue the use of any hormone-based medications, such as oral contraceptives, utilize Sun protection methods year round, and switch to mild cleansers and cosmetics to avoid triggering the condition. Therapies that have shown to be effective in inhibiting the formation of new pigmentation include bleaching creams such as hydroquinone, azelaic acid and kojic acid, and topical corticosteroids. Treatments which remove existing pigment include salicylic acid creams, topical alphahydroxy acids, Topical retinoids, derm- and microdermabrasions (though this may darken the affected area in some cases) and laser resurfacing. Also effective in the destruction of pigment is a pigment laser or IPL therapy, which provides the quickest results. Any treatment prescribed will take some time to be effective, and even then, only 1/3 of affected persons will see a complete cure effected, and even then areas of pigment may recur with exposure to triggers.