How to treat post-inflammatory hyperpigmentation like a dermatologist Post-inflammatory hyperpigmentation (PIH) is a skin condition that occurs after pimples resolve, leaving behind tan or brown post-acne marks which can last months to years (and is really common in people with melanated skin). Here are 3 tips to help prevent PIH and help fade these marks faster: 1. Don’t pop or pick at pimples - this can leave permanent dark marks or scarring. Instead to heal pimples, try spot treatments contai