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Postinflammatory hyperpigmentation, or PIH, is the medical term given to discoloration of the skin that follows an inflammatory wound. It is the skin's natural response to inflammation. PIH presents itself as a flat area of discoloration on the skin (macule) ranging from pink to red, purple, brown or black, depending on skin type and depth of the discoloration. PIH is characterized by an acquired increase in cutaneous pigmentation secondary to an inflammatory process. Excess pigment deposition may occur in the epidermis or in both the epidermis and the dermis [1]. PIH is very common among acne sufferers. It can occur in all skin types, although it is more common in darker skin types. It affects both men and women equally. PIH is not a true scar. Postinflammatory hyperpigmentation may be a sequela of conditions such as acne, allergic reactions, drug eruptions, papulosquamous disorders, eczematoid disorders, and vesiculobullous disorders etc [2,3]. PIH is caused by 1 of 2 mechanisms that result in either epidermal melanosis or dermal melanosis. The epidermal inflammatory response results in the release and subsequent oxidation of arachidonic acid to prostaglandins, leukotrienes, and other products. These products of inflammation alter the activity of both immune cells and melanocytes. Specifically, these inflammatory products stimulate epidermal melanocytes, causing them to increase the synthesis of melanin and subsequently to increase the transfer...