Post-Inflammatory Hyperpigmentation vs. Post-Inflammatory Erythema (PIH vs. PIE)

SPEED DIAL #41

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Post-Inflammatory Hyperpigmentation (PIH) and Post-Inflammatory Erythema (PIE) are 2 types of pigmentation scars leftover from acne (or other skin trauma). People often refer to everything as PIH, and while it gets the point across and many products can work for both, the distinction matters in terms of what you are actually trying to address—especially since only one of them is actually pigment. Both take time to fade and you can have both.