What Causes Acne Scars? Dermatologists Explain

person with acne and scars

Stocksy

Most zits are temporary annoyances that disappear with salicylic acid, a retinoid, a little concealer, and a ton of patience. So it's too bad that acne scars can last for months, years, and even decades after the memories of the pimples themselves have faded.

But you don't have to be resigned to living with your acne scars into retirement. There are plenty of skincare products and professional treatments to help minimize acne scars, no matter how old, wide, or deep those bad boys are.

We spoke to experts to find out how you get acne scars; why some breakouts scar while others practically vanish within days; and what you can do to prevent scars and treat the ones you have.

Keep reading to learn, once and for all, how you get acne scars.

What Causes Acne Scars

So how do you get acne scars? Ciraldo says scars occur because of inflammation. Inflammation can usually be traced to:

  • Picking skin
  • Untreated acne
  • Genetic predisposition

Ciraldo adds that picking and popping blemishes "accounts for the majority of acne scars" she sees in patients. Those scars fall into four categories:

  • Rolling scars occur when "skin heals with an uneven, wavy contour" after "moderate to severe acne."
  • Ice-pick scars leave skin with a "linear depression" ("sort of like a cut that wasn't stitched up," she explains).
  • Boxcar scars are box-like scars that leave a "wider, depressed" scar.
  • Keloid scars occur when the skin produces too much collagen, giving scars a raised appearance.

BTW, those annoying red and brown marks you get when a pimple heals are not scars. "We reserve the term 'acne scar' for true scar tissue," Ciraldo says; discoloration from acne is called post-inflammatory hyperpigmentation.

Are Some People More Prone to Acne Scars?

For some people, scarring is, unfortunately, a genetic factor. "There are definitely families that have a genetic tendency to bad scarring," Ciraldo says, pointing to the hereditary nature of issues like hyperpigmentation and keloid scarring.

Keloid scarring, in particular, is more common in certain ethnic populations. "Keloids are more common in both dark skin as well as Asian skin," Ciraldo says, adding that fair-skinned redheads are also prone to keloids.

If your parents or siblings have a history of scarring or struggle with post-inflammatory hyperpigmentation, it's all the more important that you chat with a derm. "It is essential to see a dermatologist for guidance on acne treatment and how to treat any acne scars that may form," she insists.

Why Don't All Breakouts Scar?

When you get an absolute unit of a zit on your chin, you never know whether it will go away quietly in a week or haunt you for years. So why do some pimples scar and others don't?

"There has to be significant inflammation in order for acne to scar," Ciraldo explains. "When the skin is inflamed, extra blood cells move into the area. These cells turn on an enzyme production that includes specific wound-healing enzymes to produce collagen."

If your collagen functions normally, your skin doesn't scar. But sometimes, "collagen-inhibiting enzymes, so-called MMPI enzymes," mess with collagen production, Ciraldo explains. That's when you get a scar.

Cystic acne is the type of acne most likely to leave scars. “In general, acne that scars tend to be pustular or cystic because it is infected," Green says. "Comedonal acne, which mostly consists of whiteheads or blackheads, is much less likely to scar.”

However, picking at your skin when you have a whitehead or a blackhead increases inflammation, boosting your odds of getting a scar.

How to Avoid Acne Scars

The best way to stop acne scarring is to stop acne before it starts. "I strongly recommend getting on an acne regimen if you are breaking out to both resolve existing acne ASAP and prevent new acne from forming to minimize the risk of scarring," Ciraldo says.

Pick a face cleanser and/or toner with blemish-busting benzoyl peroxide or salicylic acid. Peace Out Blemish Balm features salicylic acid plus niacinamide and lactic acid, which help fade post-inflammatory hyperpigmentation.

peace out blemish balm cleanser
Peace Out Blemish Balm $22
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We also love Farmacy Deep Sweep 2% BHA Pore-Cleaning Toner, which uses salicylic acid to leave pores squeaky-clean and has papaya enzyme to brighten skin.

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Farmacy Deep Sweep 2% BHA Pore Cleaning Toner $28
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Lastly, treat your zits with a powerful but gentle acne treatment like AcneFree Adapalene Gel, a prescription-strength product now available to buy over the counter.

acnefree adapalene gel
AcneFree Adapalene Gel $12
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If your acne doesn't chill after a few months using over-the-counter acne products, talk to your dermatologist about prescription medications for acne prevention. "Oral antibiotics, retinoids, Accutane, or a hormonal treatment such as spironolactone or birth control pills may be helpful," Green says.

You may still get a big, angry zit every once in a while, but there are steps you can take to prevent scarring. Ciraldo suggests applying a 1 percent hydrocortisone cream to inflamed pimples and applying ice 10 minutes at a time, two to three times a day.

Getting a cortisone injection at your dermatologist's office is also a quick solution to flattening an inflamed pimple, but it comes with its own risks. "If you get a cortisone shot into facial acne, there is a risk of getting a long-standing dimpling or depression from the shot," Ciraldo explains.

How to Treat Acne Scars

So do acne scars ever go away? Sure—with help from a great skincare routine and, potentially, a dermatologist, scars can fade or disappear altogether. Here are treatments to try.

Peels

If you have mild or moderate acne scarring, Ciraldo recommends visiting a skin care professional for glycolic or trichloroacetic (TCA) peels. Ciraldo is a fan of 70 percent glycolic acid peels—often called "lunchtime peels"—because they require "no real downtime."

"A series of these done weekly for six to eight weeks can give impressive, visible improvement for both acne and mild acne scarring," she says.

TCA peels ranging from 25 to 35 percent concentration are great for "more moderate acne scarring" or older acne scars, which are more challenging to eliminate, she says.

Peels can improve acne scars on all skin tones, but those with dark skin should proceed with caution before getting TCA peels. "It is best to ask for a test patch to be treated to be sure that there is no post-inflammatory hyperpigmentation," Ciraldo recommends.

Fillers

Pitted acne scars—new or old—can be injected with hyaluronic acid filler, a quick though impermanent way to smooth over scars on all skin types.

“Very deep scars can be filled since the collagen has been lost due to the scarring,” Green says. “Depending on the depth and type of scars, there are different fillers like Bellafill, Restylane, and Sculptra that are very effective."

Microneedling

If you have deep or long-standing acne scars—think: scars from breakouts years ago—consider microneedling, which boosts collagen production by creating microscopic injuries in the face using small needles. It's also safe for a variety of skin tones.

"I’m in love with microneedling with radio frequency," Vargas raves. "Nothing corrects and remodels collagen better and we have done it in my office on all skin tones. It has been something I have come to rely on."

"Microneedling was originated in Asia and is generally well tolerated by Asian and Black skin," Ciraldo adds, "but I recommend these skin types start with a shorter needle length and slower speed adjustment."

Lasers

For severe scarring or old acne scars, you can also try the big guns: lasers. "Lasers such as Fraxel and eMatrix Radiofrequency laser are amazing at smoothing out the texture," Green says. "Red scars and keloidal scars respond best to the V-beam laser since it is the gold standard for reducing redness and eliminating them."

Once again, if you have darker skin, it's a good idea to ask your derm for a patch test before going all-in with lasers.

Sunscreen

Protecting yourself from sun exposure speeds skin healing of acne scars, so never skimp on sunscreen.

"If you get too much sun and create a sunburn reaction, the persistent inflammation can accelerate scarring," Ciraldo says. "I generally say only get sun with SPF 30 to 50 on your face."

We love Emma Lewisham Skin Shield SPF 30, a broad-spectrum zinc oxide sunscreen that pampers skin with hydrating hyaluronic acid and soothing plant extracts.

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Skincare Products

If you've had acne scars for under a year, Ciraldo says you can minimize them with some key skincare ingredients.

First, put vitamin C in your skincare rotation. "Topical vitamin C stimulates collagen production and also helps to brighten skin and fade hyperpigmentation," Ciraldo says. Biossance Squalane + Vitamin C Dark Spot Serum combines vitamin C with hyperpigmentation-fighting licorice root and white shiitake mushroom extracts.

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Biossance Squalane + Vitamin C Dark Spot Serum $62
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Ciraldo also recommends using peel pads or toners with a 10 percent concentration of glycolic acid. Glycolic acid can "help to unclog pores and minimize acne, and it also supports new healthy collagen production," she says. "Our Dr. Loretta Micro Peel Peptide Pads are a great product for this."

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Dr. Loretta Micro Peel Peptide Pads $60
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Retinoids not only help prevent acne, they can improve mild acne scarring. According to Vargas, retinoids correct "structural changes from acne in the collagen by stimulating normal, healthy cell turnover. This, over time, can help remodel the damaged collagen and correct the scar."

The most powerful retinoids are available by prescription, but less potent retinol products can be purchased over the counter.

The Final Takeaway

Acne scars are a common annoyance, but with a smart skincare plan, you don't need to be stuck with them forever. Fade and prevent acne scars with in-office treatments and a solid skin care routine.

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