Some people develop dark marks after acne spots have healed. This is known as post-inflammatory hyperpigmentation or PIH. These spots are not acne scars.
Who gets these: PIH can affect anyone but is more common in people with darker skin. A study of acne in skin of colour found 65% of African-Americans, 52% of Hispanics and 47% of Asian acne patients developed PIH.
Causes – Acne causes inflammation of the skin including redness around spots, pus and tenderness. Skin cells damaged during this process become over active and release more of a skin pigment called melanin. This over reaction is likely an inherited trait.
Don’t make it worse. Squeezing and picking spots can increase inflammation (redness) and makes PIH worse.
Top tip: Sun exposure makes dark marks or PIH even darker. To avoid worsening the condition, practice great sun protection including wearing sunscreen, hats and clothing and limit sun exposure.
Treatment. This long lasting condition can be treated more easily and effectively than true scarring.