This is the Best Ingredient for Acne and Redness — And You're Probably Not Using It

As someone who's struggled with stubborn breakouts for most of their adult life thus far, I've tried every over-the-counter acne-fighting ingredient I could get my hands on — or so I thought. Even though as a beauty editor I'm tuned into the latest products and "it" ingredients on the market, using azelaic acid for pimples and redness from rosacea somehow slipped under my radar.

I was first turned onto azelaic acid when a post from a Facebook skincare group about how well it worked for treating acne was passed onto me. This led me down a deep Reddit hole where I found that there were entire threads dedicated to the ingredient.

The reason why so many people on the internet swear by azelaic acid is that the ingredient has antibacterial proprieties that help calm and prevent pimples and inflammation, plus it's an exfoliant that can lighten up dark spots from old breakouts over time so your skin tone appears more even.

To get the complete lowdown on this overlooked skincare ingredient, I turned to board-certified cosmetic and medical dermatologist Dr. Lily Talakoub to find out how and why azelaic acid works, what skin types it's best for, and more.

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What Is Azelaic Acid, and How Does it Work?

"Azelaic acid is called a dicaboxylic acid, which is derived from yeast in wheat, rye, and barley," says Dr. Talakoub. "It is also produced by yeast on the skin." It's an exfoliant like AHA and BHA acids, two common ingredients in acne products, but these are usually derived from fruit acids or made synthetically.

While both AHA and BHA acids are great for exfoliation and promoting skin cell turnover, aczelaic acid is also antibacterial. This means that it can be extremely effective at keeping the bacteria that causes acne under control, plus calms inflammation and redness. "Azelaic acid works by killing bacteria on the skin, as well as decreasing keratin which clogs pores," confirms Dr. Talakoub. "It has an anti-inflammatory property which will decreases redness and swelling associated with rosacea."

Who Can Use Azelaic Acid?

This ingredient is safe for all skin types, including expectant mothers. However, according to Dr. Talakoub, acne-prone skin, people with rosacea, or hyperpigmentation would benefit the most from using azelaic acid.

How Often Should You Use It and What Are the Side Effects?

Dr. Talakoub says that azelaic acid should only be used once a day. "It can have a slight tingle when applied to the skin and should be used very cautiously in sensitive or inflamed skin."

If overused, azelaic acid can lead to irritated, red skin. To prevent any side effects, start by using it once every other day for a few weeks to see how your skin reacts to it, and then work your way up to everyday.

Like with AHA and BHA acids, if you use azelaic acid in the morning, it's best to apply sunscreen afterwards because the ingredient can make your skin more sensitive to sunlight.

Dr. Talakoub recommends not using AHA and BHA acids when you're using azelaic acids because, together, these ingredients could be too harsh for your skin. As for retinol, she says it can be used in combination with oily and acne-prone skin, but should be avoided if you have rosacea or inflamed skin.

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It Comes in Prescription and Non-Prescription Form

Prescription azelaic acid usually comes in a 15 percent concentration, but is also available in 20 percent, too. A systematic review of the clinical trials of both concentrations published in JAMA Dermatology in 2006 found that both concentrations were effective in treating rosacea symptoms, specifically papules and pustules.

As for over-the-counter options, they'll have lower concentrations of the ingredient that while will work, may not be as effective as a prescription. There's currently two cult-favorite products with azelaic acid in them that people on Reddit and Facebook swear by.

The Ordinary's Azelaic Acid Suspension 10% is a gel-cream with a high concentration of the acid that can be applied AM or PM. It works to brighten skin while improving texture and minimizing blemishes. Oh, and a tube of it will only set you back $8.

Alternatively, Paula's Choice Azelaic Acid Booster contains 10% azelaic acid among other other exfoliating extracts and hydrators. The gel-cream can be used alone, or added to your favorite moisturizer or serum.

The bottom line: While azelaic acid may be effect for treating acne and roscea symptoms, it's best to introduce a new skincare ingredient into your routine with caution to prevent irritation and redness.