Topical treatment for postinflammatory hyperpigmentation: a systematic review.

Retinoids, hydroxy acids and broad-spectrum sunscreen were supported by the greatest number of high-quality studies. Ongoing inflammation may be subtle, especially in darker skin phenotypes. Herein, we proposed an evidence-based algorithm for PIH based on the high-quality studies. There is a need to adopt a validated outcome measure for PIH to better compare efficacy between various treatments in future studies.