INTRODUCTION
Pigmentary disorders (particularly melasma, postinflammatory hyperpigmentation, and solar lentigines) are among the most common skin disorders, impacting patient quality of life, perception by others, and even self-perception.1,2 Hyperpigmentation results from excess production of melanin induced by dysregulation of a multi-step synthesis process that converts tyrosine to L-DOPA via tyrosinase activity, eventually producing eumelanin and pheomelanin, which are deposited at the dermal and epidermal layers of skin.3
Excess melanin production may be initiated in response to skin injury, inflammation, certain medications, and sun exposure.4 Melanin confers skin pigmentation and affords some protection to the skin from ultraviolet radiation.5 Prolonged sun exposure stimulates melanogenesis, which generates superoxide and hydrogen peroxide, reactive oxygen species that can cause DNA damage and trigger inflammation, further upregulating melanogenesis.6,7 Additionally, in patients with inflammatory skin conditions, the levels of antioxidants, which neutralize reactive oxygen species, can be lower than in patients with healthy skin.8 As a result of the impact of prolonged sun exposure on excess melanin production, a fundamental aspect of hyperpigmentation management is the use of photoprotection (eg, photoprotective clothing, sunglasses, and topical application of sunscreen) to prevent worsening appearance of hyperpigmentation.9 Specifically, the use of broad-spectrum sunscreens with SPF is recommended as the standard of care for arresting hyperpigmentation, particularly sunscreens that provide visible light protection using iron oxide and/or neutralize reactive oxygen species using antioxidants.10-12 Common active treatments for hyperpigmentation (treatments that seek to reverse hyperpigmentation rather than just prevent further hyperpigmentation) include hydroquinone (often considered the most effective ingredient for hyperpigmentation), retinoids, kojic acid, chemical peels, laser therapy, and oral tranexamic acid, which have demonstrated some efficacy, but carry the risk of adverse effects and may not be as accessible as over-the-counter products due to price or the need for a doctor's visit or a prescription.9
Excess melanin production may be initiated in response to skin injury, inflammation, certain medications, and sun exposure.4 Melanin confers skin pigmentation and affords some protection to the skin from ultraviolet radiation.5 Prolonged sun exposure stimulates melanogenesis, which generates superoxide and hydrogen peroxide, reactive oxygen species that can cause DNA damage and trigger inflammation, further upregulating melanogenesis.6,7 Additionally, in patients with inflammatory skin conditions, the levels of antioxidants, which neutralize reactive oxygen species, can be lower than in patients with healthy skin.8 As a result of the impact of prolonged sun exposure on excess melanin production, a fundamental aspect of hyperpigmentation management is the use of photoprotection (eg, photoprotective clothing, sunglasses, and topical application of sunscreen) to prevent worsening appearance of hyperpigmentation.9 Specifically, the use of broad-spectrum sunscreens with SPF is recommended as the standard of care for arresting hyperpigmentation, particularly sunscreens that provide visible light protection using iron oxide and/or neutralize reactive oxygen species using antioxidants.10-12 Common active treatments for hyperpigmentation (treatments that seek to reverse hyperpigmentation rather than just prevent further hyperpigmentation) include hydroquinone (often considered the most effective ingredient for hyperpigmentation), retinoids, kojic acid, chemical peels, laser therapy, and oral tranexamic acid, which have demonstrated some efficacy, but carry the risk of adverse effects and may not be as accessible as over-the-counter products due to price or the need for a doctor's visit or a prescription.9
