Topical treatments are widely used for the treatment of post-inflammatory hyperpigmentation (PIH). However, the quality of evidence supporting these treatments has been poorly evaluated. A systematic review assessed the evidence for topical medications in treating PIH.

This review selected English-language studies evaluating topical medications for PIH via searches through PubMed, MEDLINE and EMBASE, until March 2021. The quality of evidence was assessed using the modified Grading of Recommendations, Assessment, Development and Evaluation scale (GRADE).

Overall, 47 studies involving 1,853 subjects were included. High-quality studies supported the use of retinoids, hydroxy acids, corticosteroids, thiamidol, niacinamide and plant-derived products as effective topical agents for PIH were selected. Almost all studies recommended the use of broad-spectrum sunscreen with a minimum SPF30. Common side effects of topical treatments included desquamation, burning, stinging, dryness and pruritus.

The findings depicted topical agents in high-quality studies included retinoids, hydroxy acids, corticosteroids, thiamidol, niacinamide, and plant-derived products. Sunscreens with SPF30 or greater have the strongest evidence for treating PIH. It is important to note that ongoing inflammation may be subtle, particularly in individuals with darker skin phenotypes.

Source:Tan MG, Kim WB, Jo CE, Nabieva K, Kirshen C, Ortiz AE. Topical treatment for postinflammatory hyperpigmentation: a systematic review. J Dermatolog Treat. 2022;33(5):2518-26.