Hyperpigmentation is a common, harmless condition where patches of skin become darker in color than the normal surrounding skin. This darkening occurs when excess melanin, the brown pigment that produces normal skin color, forms deposits in the skin. People with darker skin tones are more prone to hyperpigmentation, especially with excess sun exposure and after inflammatory events.
Sun exposure triggers the production of melanin and is the primary risk factor in the development or exacerbation of most cases of hyperpigmentation. Hyperpigmentation can also be caused by various drugs, including some antibiotics, antiarrhythmics, and antimalarial drugs.
There are several types of hyperpigmentation:
Solar lentigines (liver spots)
Age spots (seborrheic keratosis)
Melasma or chloasma – hormonally influenced and most commonly triggered by pregnancy
Post-inflammatory hyperpigmentation resulting from a skin trauma such as acne, a bug bite or other injury or inflammatory event
While hyperpigmentation is not dangerous, many people seek treatment for cosmetic reasons. Treatments include:
Hydroquinone – this is a topical cream that works by inhibiting tyrosinase to prevent melanin synthesis, thereby lightening the skin. While there are some over-the-counter products, you can get a more potent product by prescription.
Tretinoin and corticosteroids – these topical applications enhance the skin lightening effects of hydroquinone
Azelic acid or Kojic acid
Procedures administered by a dermatologist, such as chemical peels, microdermabrasion, dermabrasion, laser treatment, or a light-based therapy
To prevent hyperpigmentation, be sure to limit sun exposure. Wear a broad-brimmed hat and use a sunscreen with an SPF 30 or higher at all times. Sunscreens containing the physical blockers zinc oxide, iron oxide and/or titanium dioxide are also helpful in blocking UV rays.