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Hyperpigmentation ¦â¯À·t¨I
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Most hyperpigmentation involve the overproduction of melanin.
Melanin is a pigment produced by melanocytes.
Melasma
Hyerpigmentary disorder of the skin characterized by dark spots or blotches on the face, forehead and neck. It occurs in 50 to 70% of pregnant women. It is triggered by both sun exposure and hormonal changes during pregnancy.
Solar Lentigo
Solar Lentigines, also called sun, age, or liver spots, are begin flat brown spots that look like large brown freckles. They appear on sun-exposed skin, such as the face or back of the hands. 90% of light skinned people over the age of 60 develop the condition. In general, those who are most likely to have solar lentigines are people who have a tendency to sunburn and tan little or not at all. It is a skin condition caused by chronic exposure to the sun or UV rays.
Blemishes
Blemishes are marks or areas of discoloration on the skin. In some cases, acne such as whiteheads, blackheads, and pimples may also be referred to as blemishes.
Some blemishes, such as port-wine stains, are discolorations a person is born with. Other blemishes, particularly acne, are caused by clogged pores. These are often caused by toiletries and cosmetics, particularly night creams, foundations, and moisturizers. Those cosmetics that are most likely to cause blemishes are reffered to as comedogenics. Therefore, anyone with a predisposition to blemishes should only use cosmetics labeled as non-comedogenic.
Stress and hormonal changes can also cause blemishes. In particular, a hormone called androgen can result in blemishes when it becomes particularly active. This is because the hormone increases production of sebum, the skin¡¦s natural oil. As this oil accumulates, it increases the chance for bacteria to grow and clog the pores.
Women are particularly prone to hormonal changes when they enter adulthood and menopause. They are also more likely to develop blemishes during pregnancy or menstruation because of the related hormonal changes.
Others abnormal skin pigmentation birthmarks, macular stains, hemangioma , port wine stains and albinism.
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