(Picture Cr: navanskincare)
Post-inflammatory hyperpigmentation (PIH), the dark spots or red spots that are left after acne lesions heal, develops when the inflammation inherent in acne lesions causes skin cells to produce more melanin, which is the pigment that gives skin its color. An increased amount of melanin makes the skin appear darker. These marks are sometimes referred to as “macules” and can last for months or even years in some cases.