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    Skin ConditionsP

    PIH (Post-Inflammatory Hyperpigmentation)

    Definition

    Dark spots left behind after a pimple, rash, or skin injury heals — caused by excess melanin produced during the body's inflammation response. Not the same as a scar.

    PIH (post-inflammatory hyperpigmentation) is the flat brown, purple, or gray mark left after the skin heals from inflammation — acne being the most common cause. It's a pigment problem, not a texture problem: the skin's surface is smooth, but melanocytes (the cells that make pigment) overproduce melanin during healing.

    PIH vs. Acne Scars

    True acne scars are textural — indentations or raised areas where tissue was damaged. PIH is flat discoloration. The good news: PIH will fade over months on its own; treatments like chemical peels, microneedling, and PiQo4 toning can dramatically accelerate that timeline.

    ⚠️ ImportantPicking at active breakouts is the #1 cause of severe PIH. Hands off, SPF on.