Melasma has such a high recurrence rate that, once the facial hyperpigmentation has been cleared, it’s best that treatment never entirely stops, Amit G. Pandya, MD, said at the virtual annual meeting of the American Academy of Dermatology.
Dr. Amit G. Pandya
He recommended alternating between a less-intensive maintenance therapy regimen in the winter months and an acute care regimen in the sunnier summer months. But . And that is largely a matter of location.
Location, location, location
Melasma has a distinctive symmetric bilateral distribution: “Melasma likes the central area of the forehead, whereas the lateral areas of the forehead are more involved in lichen planus pigmentosus. Melanoma likes the area above the eyebrow or under the eyebrow. However, it does not go below the superior orbital rim or above the inferior orbital rim,”said Dr. Pandya, a dermatologist at the Palo Alto Medical Foundation in Sunnyvale, Calif., who is also on the faculty at the University of Texas Southwestern Medical Center, Dallas.
Melasma is common on the bridge of the nose, but usually not along the nasolabial fold, where hyperpigmentation is much more likely to be due to seborrheic dermatitis or drug-induced hyperpigmentation. Melasma doesn’t affect the tip of the nose; that’s more likely a sign of sarcoidosis or drug-induced hyperpigmentation. Melasma is common on the zygomatic prominence, while acanthosis nigricans favors the concave area below the zygomatic prominence. And melasma stays above the mandible; pigmentation below the mandible is more suggestive of poikiloderma of Civatte. Lentigines are scattered broadly across sun-exposed areas of the face. They also tend to be less symmetrical than melasma, the dermatologist continued.
Acute treatment
Dr. Pandya’s acute treatment algorithm begins with topical 4% hydroquinone in patients who’ve never been on it before. A response to the drug, which blocks the tyrosine-to-melanin pathway, takes 4-6 weeks, with maximum effect not seen until 3-6 months or longer. Bluish-grey ochronosis is a rare side effect at the 4% concentration but becomes more common at higher concentrations or when the drug is used in combination therapy.
“Hydroquinone is a workhorse, the oldest and most effective depigmenting agent,” he said.
If the patient hasn’t responded positively by 3 months, Dr. Pandya moves on to daily use of the triple-drug combination of fluocinolone acetonide 0.01%/hydroquinone 4%/tretinoin 0.05% known as Tri-Luma, a kinder, gentler descendant of the 45-year-old Kligman-Willis compounded formula comprised of 0.1% dexamethasone, 5% hydroquinone, and 0.1% tretinoin.
If Tri-Luma also proves ineffective, Dr. Pandya turns to oral tranexamic acid. This is off-label therapy for the drug, a plasmin inhibitor, which is approved for the treatment of menorrhagia. But oral tranexamic acid is widely used for treatment of melasma in East Asia, and Dr. Pandya and others have evaluated it in placebo-controlled clinical trials. His conclusion is that oral tranexamic acid appears to be safe and effective for treatment of melasma.
“The drug is not approved for melasma, it’s approved for menorrhagia, so every doctor has to decide how much risk they want to take. The evidence suggests 500 mg per day is a good dose,” he said.
The collective clinical trials experience with oral tranexamic acid for melasma shows a side effect profile consisting of mild GI upset, headache, and myalgia. While increased thromboembolic risk is a theoretic concern, it hasn’t been an issue in the published studies, which typically exclude patients with a history of thromboembolic disease from enrollment. Patient satisfaction with the oral agent is high, according to Dr. Pandya.
In one randomized, open-label, 40-patient study, oral tranexamic acid plus a triple-combination cream featuring fluocinolone 0.01%, hydroquinone 2%, and tretinoin 0.05%, applied once a day, was significantly more effective and faster-acting than the topical therapy alone. At 8 weeks, the dual-therapy group averaged an 88% improvement in the Melasma Activity and Severity Index (MASI) scores, compared with 55% with the topical therapy alone (Indian J Dermatol. Sep-Oct 2015;60[5]:520).
Cysteamine 5% cream, which is available over the counter as Cyspera but is pricey, showed promising efficacy in a 40-patient, randomized, double-blind trial (J Dermatolog Treat. 2018 Mar;29[2]:182-9). Dr. Pandya said he’s looking forward to seeing further studies.
Chemical peels can be used, but multiple treatment sessions using a superficial peeling agent are required, and even then “the efficacy is usually not profound,” according to Dr. Pandya. Together with two colleagues he recently published a comprehensive systematic review of 113 published studies of all treatments for melasma in nearly 7,000 patients (Am J Clin Dermatol. 2020 Apr;21(2):173-225).
Newer lasers with various pulse lengths, fluences, wave lengths, and treatment frequency show “some promise,” but there have also been published reports of hypopigmentation and rebound hyperpigmentation. The optimal laser regimen remains elusive, he said.
Maintenance therapy
Dr. Pandya usually switches from hydroquinone to a different topical tyrosinase inhibitor for maintenance therapy, such as kojic acid, arbutin, or azelaic acid, all available OTC in many formulations. Alternatively, he might drop down to 2% hydroquinone for the winter months. Another option is triple-combination cream applied two or three times per week. A topical formulation of tranexamic acid is available, but studies of this agent in patients with melasma have yielded mixed results.
“I don’t think topical tranexamic acid is going to harm the patient, but I don’t think the efficacy is as good as with oral tranexamic acid,” he said.
Slap that melasma in irons
A comprehensive melasma management plan requires year-round frequent daily application of a broad spectrum sunscreen. And since it’s now evident that visible-wavelength light can worsen melasma through mechanisms similar to UVA and UVB, which are long recognized as the major drivers of the hyperpigmentation disorder, serious consideration should be given to the use of a tinted broad-spectrum sunscreen or makeup containing more than 3% iron oxide, which blocks visible light. In contrast, zinc oxide does not, Dr. Pandya noted.
In one influential study, aminolevulinic acid was applied on the arms of 20 patients; two sunscreens were applied on areas where the ALA was applied, and on one area, no sunscreen was applied. The minimal phototoxic dose of visible blue light was doubled with application of a broad-spectrum sunscreen containing titanium dioxide, zinc oxide, and 0.2% iron oxide, compared with no sunscreen, but increased 21-fold using a sunscreen containing titanium dioxide, zinc oxide, and 3.2% iron oxide (Dermatol Surg. 2008 Nov;34[11]:1469-76).
Moreover, in a double-blind, randomized trial including 61 patients with melasma, all on background 4% hydroquinone, those assigned to a broad-spectrum sunscreen containing iron oxide had a 78% improvement in MASI scores at 8 weeks, compared with a 62% improvement with a broad-spectrum UV-only sunscreen. Both sunscreens had a sun protection factor of at least 50 (Photodermatol Photoimmunol Photomed. 2014 Feb;30[1]:35-42).
Numerous sunscreen and makeup products containing more than 3% iron oxide are available OTC in various tints. It’s a matter of finding a color that matches the patient’s skin.
Concern has been raised that exposure to the visible blue light emitted by computer screens and cell phones could worsen melasma. Dr. Pandya noted that reassurance on that score was recently provided by French investigators. They measured the intensity of visible light at the wavelengths emitted by computer screens and laptops and determined that it was 100- to 1,000-fold less than sunlight in the same spectrum. They also conducted a prospective, randomized, split-face trial in 12 melasma patients. One side of the face was exposed to the visible blue light at the same wavelengths emitted by device screens, but at far greater intensity. Blinded evaluators found no split-face difference in modified MASI scores.
“These results suggest that at a 20-cm distance, a maximized use of a high-intensity computer screen for 8 hours per day during a 5-day period does not worsen melasma lesions. Although it is very unlikely that similar exposure during a longer period would start to affect melasma lesions, such a possibility cannot be ruled out,” according to the investigators (J Am Acad Dermatol. 2019 Dec 27;S0190-9622(19)33324-9. doi: 10.1016/j.jaad.2019.12.047).
Dr. Pandya reported serving as a consultant to Incyte, Pfizer, Viela Bio, and Villaris.