INTRODUCTION
Melasma is a chronic hyperpigmentation disorder that affects approximately 1% of the general population and up to 1 in 2.5 people in high-risk groups and poses a major therapeutic challenge for dermatologists. This disorder appears as dark brown or gray-brown patches symmetrically on the face, especially on the cheeks, forehead, nose, and upper lip. Melasma has a multifactorial etiology including a combination of genetic predisposition, hormonal factors, ultraviolet radiation, skin phototype, and different environmental factors.1-3
Genetic predisposition is a major cause of melasma: 48% to 64% of affected individuals reported a family history. Melasma is more common among women due to hormonal factors. Previous studies have also shown that taking oral contraceptives increases the chance of melasma due to drastic hormonal shifts.2 Pregnancy has also been proven to be a major cause. Between 15% and 50% of pregnant women are reported to be affected by melasma. Beyond intrinsic factors, sun exposure is a major external trigger. Ultraviolet (UV) radiation and even visible light at 415 nm from sun exposure have been identified as major triggers inducing reactive oxygen species and melanin production.
Age spots, also known as solar lentigines or liver spots, are another common type of hyperpigmentation. These flat, tan, brown, or black growths usually appear on parts of the skin that are most exposed to the sun (face, hands, shoulders, and arms). Age spots are the result of cumulative sun exposure over time, leading to the production of excess melanin in localized patches. Age spots are different from melasma in their cause, appearance, distribution, demographic prevalence,
Genetic predisposition is a major cause of melasma: 48% to 64% of affected individuals reported a family history. Melasma is more common among women due to hormonal factors. Previous studies have also shown that taking oral contraceptives increases the chance of melasma due to drastic hormonal shifts.2 Pregnancy has also been proven to be a major cause. Between 15% and 50% of pregnant women are reported to be affected by melasma. Beyond intrinsic factors, sun exposure is a major external trigger. Ultraviolet (UV) radiation and even visible light at 415 nm from sun exposure have been identified as major triggers inducing reactive oxygen species and melanin production.
Age spots, also known as solar lentigines or liver spots, are another common type of hyperpigmentation. These flat, tan, brown, or black growths usually appear on parts of the skin that are most exposed to the sun (face, hands, shoulders, and arms). Age spots are the result of cumulative sun exposure over time, leading to the production of excess melanin in localized patches. Age spots are different from melasma in their cause, appearance, distribution, demographic prevalence,
