María Monterrubio

Do you wonder why azelaic acid is so effective in the management of acne and rosacea? And whether those are the only scenarios where it does a good job? Then you are in the right place. The power of azelaic acid goes well beyond diminishing the underlying inflammation of acne and rosacea-prone skin. It’s also a good team player, easy to introduce in any skincare routine. Nonetheless, formulation matters a ton.

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Hello everyone! As some of you already know, I am one of those people with acne and rosacea-prone skin. By the end of last summer, I noticed an enhanced greasiness in my already oily T-zone and rosier, sort of flaring cheeks (with a hint of melasma). So I found that was the perfect moment to try a decent azelaic acid product (I had never used one on myself before). The results have impressed me, and I wanted to share them with you guys – that was partly the inspiration for this post 🙂 That said, azelaic acid is suitable for any skin type. So bear with me!

What is, in brief, azelaic acid?

Azelaic acid is a dicarboxylic acid. That means that it has two -COOH (carboxyl) groups, one at each side of the molecule (see the image below). Malassezia fungi are part of our cutaneous microbiome (the microorganisms that populate our skin) and produce azelaic acid.

Thus, azelaic acid is naturally present in our skin. However, there are other natural sources of azelaic acid different from animal skin: for instance, cereals such as wheat, rye, and barley.

Azelaic acid in dealing with an upset skin barrier

Even the more balanced skin will sometimes experience a disturbed skin barrier. The barrier refers to the physical, chemical, and microbial layers that form the cutaneous epithelium and protect us from environmental aggressors, infections, and excessive water loss.

Regardless of your skin type, the cutaneous barrier can eventually be upset in the presence of specific environmental conditions or other factors. Take, for example, the winter when the weather is dry (you can read more about that on my previous post, Power molecules that fortify your winter skin).

The acidic pH (4-6) of our stratum corneum (the most external, dead layer of the skin) plays a crucial role in skin homeostasis. That is, the enzymes and processes that keep the epidermis working properly only take place at that specific pH.

When the skin barrier gets disturbed, the pH increases (becomes less acidic). That occurs in inflammatory skin diseases and also when there is some temporary dis-ease in the epidermis.

Thus, an elevated pH happens not only in inflammatory conditions [such as atopic dermatitis, irritant contact dermatitis (a skin rash upon contact with certain substances), rosacea or acne] but also in aged or dry skin.

Acidification of the skin (among other mechanisms) can restore that unbalanced pH and barrier impairment (at least to some degree). Topical azelaic acid can acidify and hence strengthen the epidermal barrier. In addition, it regulates various other epidermal processes, further aiding in the treatment of different skin issues related to epidermal disfunction.

How does azelaic acid work in the skin?

Azelaic acid affects the behavior of the cells of the epidermis: 

– keratinocytes (the cellular bricks that comprise the epidermis wall and produce keratin);

– melanocytes [located in the basal layer of the epidermis (the innermost), they are in charge of producing melanin and thus giving color to your skin];

– bacteria and other microorganisms that make our skin struggle (when in the wrong quantity or conditions) or thrive (when in the right cutaneous environment).

The main proteins of the epidermis are different types of keratins. The keratins in the stratum corneum (the outermost skin layer) give it its hard, protective consistency. Azelaic acid has keratolytic properties: it helps to get rid of excess keratin. That’s why it has a mild exfoliating effect: it evens out the skin surface and works particularly well within the hair follicles. 

Inside the hair follicles, azelaic acid attenuates keratinocyte over-proliferation, and thus, keratin overproduction. That also helps diminish any inflammation within those pores (such as within a pimple). 

Deep down the hair follicles are the sebaceous glands (that secrete oil to the skin surface throughout the hair canal). Therefore, by getting rid of excess keratin, azelaic acid prevents the formation of plugs of sebum and keratin (that stick together and clog the pore). In other words, azelaic acid also has a comedolytic effect: it helps unclog pores and minimize inflammation within them. And the story does not even end there!

In addition, azelaic acid has bactericidal properties. Notably, among other bacteria (like Staphylococcus epidermidis), it kills Cutibacterium acnes, which grows within the hair follicles and causes acne. Besides, azelaic acid appears to knock off Demodex mites, which are at the heart of the pathophysiology of rosacea.

Azelaic acid can hinder the activity of some of the enzymes that drive DNA replication just before cells divide (and multiply). And that might be underneath some of its anti-proliferative and bactericidal effects.

Another notable feature of azelaic acid is that it impedes melanogenesis. It inhibits the enzyme tyrosinase, which is indispensable for melanin production within our melanocytes. That’s how azelaic acid can potentially erase the typical dark hue left on the skin, for example, after acne lesions. Wait and see now more about the properties of azelaic acid for cutaneous hyperpigmentation.

When is azelaic acid worth a try?

Post-Inflammatory Hyperpigmentation (PIH)

Cutaneous inflammation (such as that in acne pimples) can over-activate surrounding melanocytes. Those hence generate too much melanin. That excess pigment deposition resulting from inflammation is called Post-Inflammatory Hyperpigmentation (PIH). PIH is even more troublesome for people with darker skin tones. The good news is that, due to its tyrosinase-inhibiting and anti-inflammatory properties, azelaic acid can deal effectively with it.

Azelaic acid can help erase PIH resulting from acne lesions, cosmetic procedures (such as lasers), scars (such as surgical or traumatic marks), or other types of skin rashes. Always wait until the skin lesions are not active anymore before applying azelaic acid. That is, when you only see the pigment and closed scar that the inflammatory process left behind.

Melasma

That is another form of skin hyperpigmentation. It most often happens in women of reproductive age. Sexual hormones and pro-inflammatory molecules induce too much melanin production in certain melanocytes. It occurs in localized areas of the skin (such as the cheeks, nose, and upper lip region) in the form of a mask (see the image below).

Melasma happens in people whose skin does tan in the sun (you might never experience it if your skin is very fair) and can be very persistent. Pro-inflammatory molecules released in the skin upon UV, infrared and blue light exposure from the sun make it get worse.

Azelaic acid might be a good option if you have sensitive skin with melasma, and depigmenting treatments such as hydroquinone or kojic acid are too harsh or do not work for you. Indeed, azelaic acid has proved to be as effective as hydroquinone for melasma in peer-reviewed scientific studies (see references at the bottom of the article).

Thus, your melasma might fade with the consistent use of azelaic acid. And you will likely enjoy it in your skincare routine due to its gentleness and effectiveness. Just because of that, it will be easy to comply with (something crucial in cases of melasma due to its persistence).

Besides, it is safe in pregnancy, when melasma often appears.

Acne-prone skin

As I said above, azelaic acid treats the bacterial and cellular over-proliferation that occurs during acne in the affected hair follicles. It also addresses the inflammatory component of acne. And the excess oil that may result from the inflammation and thus over-activation of the sebaceous glands. 

However, azelaic acid does not target the hormonal component of acne. Nonetheless, it can be effective anyways in cases of mild to moderate acne.

It will come in handy if you have acne-prone skin but are not undergoing active acne at the moment or experience it only at certain times. Azelaic acid can aid with isolated acne flares and will help keep your skin under control!

Just so you know, controlled scientific studies showed that topical azelaic acid (20% cream) is as effective as tretinoin (retinoic acid) 0.05%, benzoyl peroxide 5%, and erythromycin 2% (all common medications for the treatment of acne).

Blackheads

The comedolytic and anti-inflammatory properties highlighted above make azelaic acid efficacious for eliminating blackheads (regardless of your skin type).

Rosacea

Topical azelaic acid is effective for rosacea. Due to its keratolytic, antimicrobial, and anti-inflammatory capabilities, it can relieve the characteristic bumps of acne rosacea and the skin swelling and redness of that and other types of rosacea. However, it won’t rid you of facial telangiectasias (dilated blood vessels) – you most probably need a laser procedure to achieve that. You can learn more about the distinct subtypes of rosacea here.

15% azelaic acid reduces the excessive amount of the cathelicidin peptide present in rosacea skin. Moreover, it diminishes the activity of an enzyme (kallikrein 5) that cleavages cathelicidin. The peptide resulting from the cleavage of cathelicidin (called LL-37) worsens the pathophysiology of rosacea. For example, LL-37 can lead to new, prone-to-dilate superficial blood vessels.

Notably, people that display higher levels of kallikrein activity tend to have more marked rosacea symptoms. Hence azelaic acid is a game-changer for those folks!

15% azelaic acid can be as effective as topical metronidazole (an antibiotic and a gold-standard treatment for rosacea). Besides, azelaic acid can be purchased over-the-counter in Europe (and up to 10% in the USA). So, if you have rosacea, don’t wait – azelaic acid can improve your life.

To even out skin tone and refine skin texture (be your skin oily, mixed, balanced, or dry)

If your skin has trouble dealing with alpha-hydroxy acids (such as glycolic acid) or can’t put up with the usual depigmenting ingredients out there to correct uneven skin tone, try azelaic acid.

To benefit from a mild peel, you may need a small percentage once a day. For depigmenting purposes, you might require something more potent (15% or greater) twice a day.

Azelaic acid smooths out the skin surface gently but remember that sunscreen is mandatory. Otherwise, all your skincare efforts will be worthless!

My experience using a 15% azelaic acid serum

You can combine azelaic acid with retinol, alpha-hydroxy acids (such as glycolic acid), and beta-hydroxy acids (salicylic acid) in your skincare routine. And that’s what I do 😉 For the most part, it is not a problematic ingredient. And it is generally well-tolerated – unless you happen to be allergic to it, something that can occur with any skincare ingredient –.

I started applying azelaic acid on my T-zone (oily, acne & rosacea-prone) and cheeks (balanced and with vascular rosacea) in the morning about two months ago.

Here is the product I chose to get started: Lumizela A15 Serum (with 15% azelaic acid) from Face Theory.

When I saw the product texture, I thought it might be too thick for me (it is not an entirely liquid serum). But it was not. After gently massaging, it gets quickly absorbed by the skin. I may experience some itchiness or redness just after applying it that goes away shortly. On the first days of usage, the itchiness was more intense. 

It leaves a matte velvety finish on the skin that I love. It does not feel tight or dry. When you apply moisturizer on top of it (you might need less moisturizer than usual if your skin is more on the oily side), the skin tone and texture tend to look more even.

For me, the best part of it is that I noticed results almost immediately: my skin discoloration (redness mainly) faded. And now I feel my skin is more balanced and less inflamed; it also helped noticeably with blackheads (on my nose) and blemishes.

I’d say that my skin does not feel as oily as it did by the end of the summer. At the same time, other areas of my skin (that are not oily) do not feel dry or tight at all.

Lumizela A15 Serum includes significant amounts of glycerin – a top-tier skin humectant –, colloidal oat – a medical-grade skin-soothing ingredient – and green tea extract (all of them included in my list of top science-proven ingredients for sensitive skin). Those ingredients might significantly contribute to the gentleness and mostly non-drying features of this high-strength azelaic acid serum for every day or every other day use.

If you try this product and notice any enhanced skin dryness, do not use it every day. That can happen, especially in the beginning, until your skin gets used to it. Introduce azelaic acid slowly in your skincare routine until you find the adequate dosage for your skin and skincare objectives (you might have to be more patient with melanin hyperpigmentation).

And that’s it! I am still loving it and plan to keep it in my skincare routine for a long time. 

Have you tried this or any other product with azelaic acid? If so, what was your experience with it? Please, let me know!

You can leave your input or any question in the comments below :-). You can also message me on Instagram (@drmariamonterrubio).

I hope this post was helpful. 

See you soon!

María

For your reference:

Cathelicidin, kallikrein 5, and serine protease activity is inhibited during treatment of rosacea with azelaic acid 15% gel. Alvin B Coda et al., J Am Acad Dermatol, 2013; 69 (4): 570-7.

Comparative study of therapeutic effects of 20% azelaic acid and hydroquinone 4% cream in the treatment of melasma. Farshi S, J Cosmet Dermatol, 2011; 10 (4): 282-7.

The efficacy and safety of azelaic acid 15% foam in the treatment of facial acne vulgaris. Peter W Hashim, J Drugs Dermatol, 2018; 17 (6): 641-645.

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