Melasma: A Persistent Puzzle and Its Triggers
Melasma is notoriously exasperating, with its brown patches emerging unexpectedly and stubbornly persisting, even when potent remedies like prescription creams and devices are employed. There are moments when you might believe you've triumphed over it, only to have it resurface. Since a permanent cure for melasma is elusive, the key lies in controlling the excess pigment – which demands knowledge of the triggers, or the elements that cause the condition to flare up.
Most melasma sufferers are familiar with the common culprits. "The primary trigger factors are genetic predisposition, female hormones – pregnancy, oral contraceptives, hormone-releasing IUDs, hormone replacement therapy – and ultraviolet radiation exposure," states Dr. Heidi Waldorf, a board-certified dermatologist in Nanuet, New York.
From a genetic perspective, "melasma predominantly affects people of color, whose melanocytes, or pigment-producing cells, are more active," remarks board-certified New York City dermatologist Dr. Michele Green. Those with medium skin tones – Fitzpatrick types III and IV – tend to be hit the hardest, but skin tones at either extreme are not immune, especially when sunlight and estrogen are involved.
Sunlight alters both the structure of epidermal and pigment cells and the chemistry of the melanin in your skin, as Dr. Waldorf explains, resulting in an immediate and long-lasting darkening effect. Intriguingly, adds Dr. Green, when the sun prompts your cells to generate additional melanin, this increase "causes the skin cells to produce more melanocytes," which then produce even more pigment, causing dark patches to appear on the nose, cheeks, and forehead. The reason for this specific pattern? Experts remain unsure.
The connection between hormones and melasma is equally complex. But as board-certified Medford, Oregon, dermatologist Dr. Laurel Geraghty summarizes, our melanocytes "have their own estrogen receptors and are stimulated to produce more pigment if there are abundant hormones circulating in the body. Estrogen is believed to be the main hormonal factor, [which is] why women are more frequently affected than men."
These prominent instigators – the ones melasma patients are aware of and either guard against or learn to manage – are not the sole forces at play, though. Ahead, dermatologists disclose seven covert triggers that should also be on your radar.
Visible Light
"Visible light can stimulate enzymes involved in the melanin production process," says Dr. Mitalee Christman, a board-certified dermatologist in Boston. These wavelengths of light, which are visible to the naked eye, are emitted by the sun, devices, and light bulbs, making them hard to avoid. "The greater the dose of visible light our skin receives, the darker the skin becomes," adds Dr. Geraghty. Because "abnormal pigmentation from visible light tends to be darker and more persistent compared to UV-induced pigmentation, it can be a significant element when we aim to improve melasma." Our prime defense: tinted sunscreens containing iron oxides "can absorb visible light and offer some protection," Dr. Christman states. A few to consider: MDSolarSciences Mineral Tinted Creme SPF 30, $32; Alastin HydraTint Pro Mineral SPF 36, $55; SkinCeuticals Physical Fusion UV Defense SPF 50, $34.
Heat
What we perceive as heat is actually the infrared (IR) energy emitted by the sun, fires, radiators, and even our own skin. "Heat increases vasodilation, causing blood vessels to open wider and flow more freely, which may introduce more of the cellular stimulators of pigmentation," explains Dr. Waldorf. Heat can also intensify inflammation, further enhancing pigment production. Besides keeping your distance when enjoying the warmth by the fire, you can safeguard your skin with an antioxidant sunscreen featuring IR protection, such as SkinMedica Total Defense + Repair. When exercising, be proactive in staying cool – sip ice water, position fans nearby, mist your face (we keep this soothing Avene spray next to the Peloton), and apply cool towels to the skin immediately after working out to "help constrict those troublesome blood vessels," says Dr. Geraghty.
Irritation
Masks. Eczema. Retinoids. Waxing. "Anything that causes injury or irritation to the epidermis has the potential to trigger melasma or worsen it," says Dr. Geraghty – a phenomenon that closely resembles postinflammatory hyperpigmentation (PIH). "There's a blurry line between [the two]," she adds. "Although these conditions can overlap and behave quite similarly, melasma, in and of itself, is believed to deteriorate with skin irritation." Call it what you like, but if you have melasma, you're likely to notice your affected areas darken following any form of skin insult.
For this reason, she adds, "dermatologists will often vigorously treat any rashes or irritation with cortisone or other soothing creams to assist those prone to melasma, as one day of rashes can contribute to pigmentation that may persist for months." Of course, preventing irritation is a far superior plan. Strengthen your moisture barrier at night with creams rich in lipids like ceramides, cholesterol, and fatty acids. And before applying a mask, "use a light moisturizer to limit the irritation from the fabric mask's borders rubbing on your skin," Dr. Christman suggests.
Related: The Ultimate Guide to Understanding and Treating Melasma
Sunglasses
Classic aviators may be the greatest offenders in this regard. "Exposure to the sun causes the metal frames to accumulate heat and then transfer it to the skin," says Dr. Green. Moreover, as anyone who has sunbathed with a foil reflector knows, metal captures rays, intensifying a tan – and melasma. The weight and rubbing of metal rims on the skin can also have an adverse effect. "It's extremely important to remove sunglasses at regular intervals and apply and reapply sunscreen under and around the sunglasses while wearing them," says Dr. Waldorf.
Medications
Common medications can trigger melasma – and we're not just referring to birth control pills. "Some anti-seizure medicines, certain diuretics, the acne medicine spironolactone – all can instigate or aggravate melasma," says Dr. Geraghty. Just like with hormone-altering drugs, the excess pigment typically subsides once you stop taking the medication (always consult your doctor before making any changes to your meds).
Thyroid Disorders
While every science enthusiast knows that correlation does not imply causation, "there are studies indicating higher rates of thyroid disorders in melasma patients compared to control groups," says Dr. Waldorf. "It could be that thyroid disease makes women more susceptible to the effects of hormones and ultraviolet rays," she hypothesizes, "or that the factors that predispose to thyroid disease also predispose to melasma."
In any case, thyroid hormones are thought to play a role in melasma. If you suspect your flares are linked to a thyroid condition, your dermatologist can refer you to an endocrinologist. "They'll work on controlling the thyroid disease through medication management while I focus on treating the hyperpigmentation caused by the melasma," says Dr. Green. "Working together guarantees the best outcomes."
Melasma Treatments
It might be the ultimate beauty paradox: even the top-notch methods dermatologists rely on to fade melasma can stimulate pigment synthesis and darken persistent patches. "Melasma is truly like the sensitive friend you're constantly worried you'll upset by doing the wrong thing," says Dr. Geraghty. In this case, that mistake could be applying an annoying brightening agent, like hydroquinone or vitamin C, or treating the skin with a laser or light-based device, like IPL, both of which emit triggering visible light and heat.
"Any laser, in the wrong hands, can exacerbate melasma with improper fluences or densities," says Dr. Christman. "The most common offender I observe are IPL treatments from med spas." Nevertheless, even when experienced providers adjust their machines to low settings and proceed cautiously, melanocytes can behave unpredictably. "I can treat melasma, with improvement, several times with a pigment, vascular, or resurfacing laser – and then the next time, same device, same patient, same parameters, and it worsens," Dr. Waldorf remarks. While she sometimes opts for her low-powered Clear + Brilliant fractional laser or even uses microdermabrasion to advance the treatment and enhance the penetration of topical products, she emphasizes that, with melasma, "no procedure is without risk."
Cautious of energy devices, some dermatologists prefer to commence treatment with superficial chemical peels, such as the Cosmelan, "which is safe and effective for all skin types," Dr. Green says, and works by "reducing the skin's melanin production by inhibiting certain enzymes." Doctors are also achieving success with the oral drug tranexamic acid (TXA). "It comes with a risk of increased blood clots, so it's not prescribed lightly, but wow, does it work," Dr. Geraghty says. "I've witnessed patients whose disfiguring melasma vanished by 70–90% within three months of therapy. It can be a game-changer when topical products, peels, lights, and careful photoprotection fail."
