How To Treat Acne Scars (Post Inflammatory Erythema & Hyperpigmentation)

Posted by Azadeh Shirazi MD on

Struggling with pimples can be incredibly frustrating, but dealing with the aftermath of a breakout can sometimes be even more distressing. One of the most widespread concerns is the presence of acne scars, and many people try different products in the hopes of getting rid of them. Oftentimes these are not true scars, but stains that can last for several months. It's possible that you've been using the wrong products for your skin concerns or simply not allowing enough time for them to fade. Acne stains can look brown or purple known as post-inflammatory hyperpigmentation (PIH) or they may be red or pink known as post-inflammatory erythema (PIE). If you find yourself confused about the differences between these conditions and how to effectively treat them, you’re not alone. 

What Are Acne Scars?

True acne scars are depressions or irregularities left in the skin from damaged collagen by acne breakouts. These scars vary in their shape and depth and are treated differently. Here is how you can identify them

1. Boxcar Scars:

Characterized by broad depressions on the skin's surface that have well-defined edges; usually round or oval in shape, resembling a boxcar or a saucer. Typically caused by inflammatory acne, such as cystic acne or nodules, which damage the collagen and elastin fibers in the skin. 

2. Ice Pick Scars

Deep, narrow, and pitted indentations on the skin's surface that resemble small, round puncture marks made by an ice pick or needle. These scars are typically caused by severe acne and result from the loss of collagen and elastin fibers in the skin during the healing process.

3. Rolling Scars

Wave-like undulations or rolling hills on the skin's surface. These scars are caused by damage to the underlying collagen fibers, which results in a tethering effect between the deeper layers of the skin and the surface. As a result, the skin appears uneven and has a wavy or rolling texture.

Treating acne scars involves in-office treatments like subcision, fillers, ablative and nonablative laser resurfacing. Check out my Youtube video below for more depth information over this topic. 

What is Post Inflammatory Erythema and How Can I Treat It?

Post inflammatory erythema, also known as PIE, are red or pink stains that appear after a pimple heals. These stains can last for months, sometime up to a year. This is caused by inflammation and damaged capillaries under the skin from cystic acne. Those with lighter skin tones are more likely to have post inflammatory erythema. Treating post inflammatory erythema includes a skincare routine that can help fade the red or pink stains. Retinols are effective ingredients to fade red stains faster found in prescription strength  Lift and Renew. If you have sensitive skin or are unable to tolerate retinols, Azelaic acid and arbutin are effective options found in Azelaic10 Serum. It’s important to note that using actives like retinol too often can cause more irritation. Be patient and allow your skin time to adjust to these products. However, if you are not noticing any changes, you may need to see your dermatologist for a more personalized treatment plan including lasers or in office treatments.

What is Hyperpigmentation and How Can I Treat It?

Hyperpigmentation refers to the dark spots that appear on the skin after a pimple heals. They aren’t red or pink, which is why it’s different from post inflammatory erythema. Those with darker skin tones have more melanin therefore more susceptible to hyperpigmentation. The overproduction of melanin is a reaction to the disruption acne causes in our skin. A consistent skincare routine is beneficial for preventing and treating hyperpigmentation. The most effective way to fade hyperpigmentation is to use sun protection as UV rays and visible light contribute to increased melanin production. It’s important to use a mineral based sunscreen with iron oxide such as Hydratint BB SPF44 to reduce exposure to a wide range of UV and visible rays.  This 3 in 1 tinted moisturizer hydrates, protects, and offers broad-spectrum coverage making it the perfect summer skincare option particularly for acne and discoloration prone skin.  Clinical ingredients such as retinols, Hydroquinone, Kojic Acid, Emblica, Bearberry, Arbutin, vitamin C, and Niacinamide are effective at lightening hyperpigmentation. One of my favorite products incorporating many of these clinical ingredients are DermaBright Pads with HQ 2%. I have a Youtube video with more in depth information over Hyperpigmentation. 

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  • i believe that
    The fact that the power of vitamins for acne is not more well known is very sad to me. Because I know that many people are needlessly suffering from embarrassing acne when they could be using vitamins

    mo on

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Dr. Azadeh Shirazi, MD is a Board-Certified Dermatologist.

Specializing in medical, surgical, and cosmetic dermatology, Dr. Shirazi received her undergraduate and medical degrees from the University Of Kentucky College of Medicine. After doing a Research Fellowship at Harvard Medical School at the Wellman Center for Photomedicine, she completed her residency training in Dermatology and Cutaneous Surgery at the prestigious Mayo Clinic in addition to completing her training in dermatology and cosmetic surgery at the University of California San Diego.

She has received multiple research scholarships from iconic institutions including Harvard University and the University Of Texas Southwestern Medical Center and has several peer-reviewed publications to her name.