Sunscreen is the Best Way to Prevent Post-Inflammatory Hyperpigmentation in Skin of Color

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A systemic review analyzed the methods for preventing trauma-induced post-inflammatory hyperpigmentation in skin of color.¹ It was found that regularly applying sunscreen, especially formulations mixed with other anti-inflammatory ingredients, was a successful prevention technique.

Darker Fitzpatrick skin types between III and VI are particularly susceptible to post-inflammatory hyperpigmentation. This is due to an increased size of melanosomes and eumelanin, as well as the quantity of melanin.²

A literature search was conducted on MEDLINE, Embase, PubMed, and Cochrane databases. Investigators used search terms including “post-inflammatory hyperpigmentation,” “hypermelanosis,” “hyperchromia,” and “dyschromia.” The review consisted of randomized controlled trials, case series and reports, observational research, and cross-sectional and case-controlled studies. More than half of the included results were randomized controlled trials, with 21% being experimental studies and 14% being case reports.

The initial search yielded 3205 articles. However, 14 studies were included, comprising 369 patients in the final sample. Over 70% of participants were female with a mean age of 38 years. Nearly half of the participants had a Fitzpatrick skin type of IV with III being the second most common type. About 95% of the post-inflammatory hyperpigmentation occurred from lasers while other cases were caused by ultraviolet-B radiation and chemical peels. The most used laser was fractional carbon dioxide.

For those that received no intervention besides a regular skincare routine, 34% successfully prevented post-inflammatory hyperpigmentation while 66% failed to prevent after 2 months of the implemented regimen.

Sunscreen was the most preventative measure, especially when combined with other anti-inflammatory ingredients like licochalcone A, L-carnitine, and avobenzone. No specific formulation or regimen was superior to the others. In two studies, a 98% and 100% success rate in preventing post-inflammatory hyperpigmentation occurred after applying sunscreen for 2 months.

Topical corticosteroids, antibiotics, epidermal growth factor, and systemic tranexamic acid were less successful. Epidermal growth factor had a 34% success rate with little difference between treatment and control groups.

With an average follow-up time of 12 weeks, tranexamic acid failed at preventing post-inflammatory hyperpigmentation from occurring, especially after 532-nm QS Nd: YAG laser treatment. However, one case report saw successful prevention in a patient who used sunscreen, tretinoin 0.05%, spironolactone 100 mg, and oral TXA 650 mg daily after damage from chemical peels.

Topical antibiotics were also unsuccessful overall. Although fusidic acid cream failed to prevent post-inflammatory hyperpigmentation, it did reduce the severity with a 2% increase in Hyperpigmentation Area and Severity Index Score after 8 weeks. Corticosteroids prevented post-inflammatory hyperpigmentation in 58% but failed to prevent it in 42%. A more notable reduction was noted with clobetasol treatment versus hydrocortisone.

Cooling air devices, which were utilized in 5% of participants, actually worsened post-inflammatory hyperpigmentation, particularly after a session of 1064-nm QS Nd: YAG laser. The half of the face that was cooled had a higher risk of developing persistent post-inflammatory hyperpigmentation.

Even though this literature focused on patients with skin of color, none of the studies included Fitzpatrick skin type VI. The investigators stressed that it is “imperative to expand research inclusivity to encompass a diverse range of ethnicities.” There was also no standardized assessment scale, which could create inconsistencies in the results. Due to these limitations, there is still a large gap in incorporating all ethnicities and at-risk populations in research surrounding the prevention of post-inflammatory hyperpigmentation.

“While photoprotection is a promising preventative strategy, an educational gap exists wherein individuals with darker skin tones lack awareness regarding the significance of sunscreen usage,” the authors concluded. “In summary, there is substantial room for improvement in this area, and there is considerable optimism for enhancing preventative strategies in the future.”

References

1. Mar K, Maazi M, Khalid B, Ahmed R, Wang OJE, Khosravi-Hafshejani T. Prevention of Post-Inflammatory Hyperpigmentation in Skin of Colour: A Systematic Review. Australas J Dermatol. Published online February 14, 2025. doi:10.1111/ajd.14432

2. Kashetsky N, Feschuk A, Pratt ME. Post-inflammatory hyperpigmentation: A systematic review of treatment outcomes. J Eur Acad Dermatol Venereol. 2024;38(3):470-479. doi:10.1111/jdv.19566