What causes Acne Scars, Dark Spots and Post-Inflammatory Hyperpigmentation?

If you have ever struggled with acne, you'll probably be familiar with those dark marks that linger for months after your acne has healed - These spots are called post-inflammatory hyperpigmentation. 

Post-Inflammatory Hyperpigmentation is the result of any inflammatory skin reaction from acne, dermatitis, psoriasis, skin infections, skin trauma, burns and drug eruptions. PIH from acne and other skin issues are made worse by picking or squeezing, and sun exposure.

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Post-inflammatory hyperpigmentation occurs when acne, or any other injury causes the skin to be inflamed. This inflammation triggers excess melanin production, leaving behind discoloration after the injury or acne has healed. Post-inflammatory hyperpigmentation will fade over time, however it can take up to two years to completely go away.

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Post-inflammatory hyperpigmentation is characterized by a flat area of discoloration of the site of injury. This coloration can range from pink, red, purple brown or black - depending on the tone and depth of your skin. The severity of the injury or acne legion also correlates to the darkness of pigmentation; the darker the spot, the longer it'll take to fade.

Post-inflammatory hyperpigmentation is very common in acne prone skin as well as deeper skin tones. Post-inflammatory hyperpigmentation is often referred to as acne scars, however these spots are not true scars. Post-inflammatory hyperpigmentation doesn't involve changes to collagen in the skin, so there is no actual scar tissue. 

Although post-inflammatory hyperpigmentation generally fades on its own, treatments such as laser genesis,  lightening creams, chemical peels, microdermabrasion, and daily sun protection can help speed up the fading process.