![]() Other factors implicated in the etiopathogenesis of melasma are photosensitizing and anticonvulsant medications, mild ovarian or thyroid dysfunction, and certain cosmetics. ![]() Genetic factors are indicated by familial occurrence of melasma and its increased incidence in people of Asian and Hispanic origins. ![]() The mechanism of induction of melasma by estrogen may be related to the presence of estrogen receptors on the melanocytes that stimulate the cells to produce more melanin. The role of female hormonal activity has been suggested by the increased frequency of occurrence of melasma in pregnancy and in those on oral contraceptive pills, estrogen replacement therapy, and estrogen treatment for prostatic cancer. The pathophysiology of melasma remains elusive, but multiple factors have been implicated. The clinical and histological features of melasma in men are the same as those of melasma in women. It is much more common in women during their reproductive years but about 10% of the cases do occur in men. Melasma is the most common pigmentary disorder among Indians. The term, “chloasma” (from the Greek word, ‘ chloazein’ meaning ‘to be green’) is often used to describe melasma developing during pregnancy however, as the pigmentation never appears to be green, the term, “melasma” should be preferred.Īlthough melasma may affect any race, it is much more common in constitutionally darker skin types (skin types IV to VI) than in lighter skin types, and it may be more common in light brown skins, especially in people of East Asian, Southeast Asian, and Hispanic origin who live in areas of the world with intense solar ultraviolet exposure. The most common locations are the cheeks, upper lips, the chin, and the forehead, but other sun-exposed areas may also occasionally be involved. It presents as symmetric, hyperpigmented macules having irregular, serrated, and geographic borders. Melasma (from the Greek word, ‘ melas’ meaning black) is a common, acquired, circumscribed hypermelanosis of sun-exposed skin. Well-designed controlled clinical trials are needed to clarify their role in the routine management of melasma. The search for safer alternatives has given rise to the development of many newer agents, several of them from natural sources. Prolonged HQ usage may lead to untoward effects like depigmentation and exogenous ochronosis. The most popular combination consists of HQ, a topical steroid, and retinoic acid. Combination therapy is the preferred mode of treatment for the synergism and reduction of untoward effects. Topical medications modify various stages of melanogenesis, the most common mode of action being inhibition of the enzyme, tyrosinase. Besides HQ, other topical agents for which varying degrees of evidence for clinical efficacy exist include azelaic acid, kojic acid, retinoids, topical steroids, glycolic acid, mequinol, and arbutin. Multiple options for topical treatment are available, of which hydroquinone (HQ) is the most commonly prescribed agent. In addition to avoidance of aggravating factors like oral pills and ultraviolet exposure, topical therapy has remained the mainstay of treatment. The management of melasma is challenging and requires a long-term treatment plan. ![]() Melasma is a common hypermelanotic disorder affecting the face that is associated with considerable psychological impacts.
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