A Guide to Azelaic Acid

Find out all you need to know about this all-star ingredient with Heather Wish, Skincare Education Specialist at Paula’s Choice.

 What is azelaic acid?

Azelaic acid is a skin-friendly dicarboxylic acid* with unique properties that deliver:

• Mild exfoliating action that helps unclog pores and refine skin’s surface

• Skin tone-evening properties that visibly fade post-acne marks and other discolourations

• Significant skin-calming factors to reduce sensitivity and bumps

• Antioxidant power that contributes to healthier-looking skin

Azelaic acid can be derived from grains like barley, wheat, and rye. However, the lab-engineered form is typically used in skincare formulas because of its greater stability and effectiveness. 

Some of the research on this ingredient has looked at prescription-only topical products with concentrations between 15% and 20%, but there are also incredible benefits to be seen at lower concentrations, such as between 5-10%.

 How does it help with hyperpigmentation?

Azelaic acid is a tyrosinase (melanin-stimulating enzyme) inhibitor and helps inhibit the synthesis of melanin-producing cells known as melanocytes, both useful for tackling hyperpigmentation, including melasma. Its anti-inflammatory action interrupts an anti-inflammatory process that plays a role in triggering excess melanin. Interestingly, research has shown this ingredient has what’s referred to as ‘selective toxicity’ against excess melanocytes that would otherwise go on to create dark spots.

An additional lightening effect could be explained through the antioxidant effect of azelaic acid by decreasing free radicals. Left unchecked, the damaging molecules trigger inflammation which in turn stimulates excess melanin production, but in an uneven pattern.

How does it reduce breakouts?

Azelaic acid has an antibacterial effect against acne-causing bacteria. It also functions as a potent anti-inflammatory, so it helps reduce the swelling and redness that often accompanies acne. Azelaic acid’s antibacterial actions make it a great alternative for those with breakouts whose skin cannot tolerate benzoyl peroxide. Research has also shown that azelaic acid (20% concentration, applied six times as a rinse-off peel) has a normalising role on sebum, which is believed to be another way its use helps control acne and improve other skin issues related to excess oil, such as seborrhea.

Azelaic acid also has an impact on excess keratinisation or the creation of too many skin cells. Within the pore lining, these skin cells can mix with sebum and debris, leading to a clog that can enlarge the pore and create a bumpy texture. As such, the use of azelaic acid can help to reduce clogged pores and give the skin a smoother texture.

Due to its impact on excess keratinization, combining azelaic acid with a leave-on BHA (salicylic acid) exfoliant tackles breakouts in different but complementary ways, so you’ll see even better results combining the two. Azelaic acid is generally well tolerated, with a surprisingly low incidence of side effects (the most common being transient stinging).

How does it reduce redness?

Azelaic acid has anti-inflammatory benefits. Specifically, it inhibits the formation of several inflammatory chemicals in the skin (cytokines) that drive signs and sensations of sensitive, reddened skin. It does this by reducing the activity of specific proteins in the skin that, left unchecked, go on to churn out an excessive amount of inflammatory cytokines. By controlling the process, azelaic acid reduces redness, including from rosacea.

Azelaic acid and pregnancy

During pregnancy, hormones can really affect the skin. Hormone fluctuations are known to have an impact on melasma’s development in the skin. Breakouts can also be more likely when pregnant. Most concerns that come with hormonal fluctuations can be addressed with azelaic acid. Topical azelaic acid has been demonstrated as safe for use during pregnancy and when breastfeeding.

The Paula’s Choice 10% Azelaic Acid booster can be used by itself or mixed with a serum, treatment, or nighttime moisturiser. You need a pea-sized amount and can use it as a treatment to target specific areas or all over the face. Azelaic acid works really well with other common skincare actives, so you can use it alongside targeted treatments to help your various concerns fast. Azelaic acid is also a gentle ingredient that’s safe for use with sensitive skin, including rosacea-prone.

Words by Heather Wish, Skincare Education Specialist at Paula’s Choice

*A substance that has two carboxyl groups as part of its molecular structure and functions as a weak acid