What Is Azelaic Acid? Use for Redness, Acne and Spots

Azelaic acid is a multi-purpose ingredient used for acne, rosacea-related redness, and some dark spots, targeting bacteria, inflammation, and pigment formation together. Most of the evidence comes from 15% gel and 20% cream forms licensed as drugs, and the use plan is determined by a doctor in these forms. Data for cosmetic products at 10% and below is much more limited. It is generally well tolerated; results take weeks.

How does azelaic acid work? Four different effects

It is a naturally occurring dicarboxylic acid, so its structure differs from the AHA or BHA group. This versatility is what makes it special; it is not an agent that targets a single goal.

• Antibacterial: It reduces bacterial numbers by blocking protein production in hair follicle bacteria.
• Keratolytic and comedolytic: It helps reduce excessive proliferation of upper-layer cells and pore blockage.
• Anti-inflammatory: It scavenges free radicals and lowers the harmful oxygen derivatives produced by inflammatory cells.
• On pigment: It suppresses the tyrosinase enzyme involved in melanin production. This is why it is used for post-inflammatory dark spots and melasma.

These mechanisms partly come from the laboratory. The place to look for judging results is clinical studies.

For which problem is azelaic acid how strong?

A systematic review examining 43 randomized studies includes 20 for rosacea, 16 for acne and 7 for melasma. Another review states that the strongest evidence is in rosacea, followed by melasma and acne. A comprehensive review specific to acne reports moderate certainty for some comparisons.

This table comes from prescription forms. Rather than "azelaic acid solves all of these problems," it is more honest to say "a good option at a specific concentration, under doctor supervision, for specific problems."

Comparisons with rivals in acne

The review of over-the-counter agents for acne highlights four comparisons for azelaic acid. In a 351-person study it was found to be probably slightly less effective than benzoyl peroxide. In a 289-person study there was no clear difference from tretinoin. The comparison with clindamycin also shows little difference, but certainty is low. The adapalene comparison remains uncertain because it was limited to 55 people. So azelaic acid does not replace a strong acne drug, but it is a reasonable option for doctors to consider for those who cannot use other options due to irritation or pregnancy.

Difference between prescription and cosmetic azelaic acid

Different forms of the same molecule exist on the market. Seen side by side they may seem the same, but their classes and the data behind them are different.

A close data point is an acne study comparing a 10% nanocrystal hydrogel with a 20% cream: success rates at week 8 were 36,5% and 30,4%. But this is a specific formulation; it cannot be generalized to every 10% product on the shelf. So you cannot say 'I use 10%, so I will get the results from the studies.' If you are considering acne, rosacea, or melasma, see a doctor first; the choice of form, ratio, and frequency is his or her decision. When using a prescription form, also ask your doctor before adding any new cosmetic active, since the combination plan is part of the treatment.

Starting with a cosmetic product

For mild uneven tone or occasional acne, if you want to try a non-prescription product, the general caution rules apply:

1. Try first. On the inner arm or elbow crease, twice a day, for 7-10 days.
2. Watch the label. If the label gives a frequency, follow it. If not, starting with 2-3 evenings a week is a cautious example; this figure is derived from the general rule, not from a study.
3. Apply to clean, dry skin. A thin layer, away from the eye and mouth area.
4. Add a moisturizer. It helps reduce dryness and stinging.
5. Do not skip morning sunscreen. It is difficult to get results from the active ingredient on spots without sunscreen. Look at correct application.
6. Evaluate for at least 12 weeks. Even with medicinal forms, the response for rosacea can take this long. Expecting results sooner from a cosmetic product is not realistic.

What might you feel in the first weeks?

Azelaic acid is generally well tolerated; because of its large molecule it may feel gentler than glycolic acid on some sensitive skin. Even so, these may occur:

• Mild stinging and itching: May be brief, right after application.
• Dryness and fine flaking: May decrease with a moisturizer and less frequent use.
• Mild irritant dermatitis: More likely on very sensitive or eczema-prone skin.
• Lightening: Unexpected lightening of the skin has been reported. It is more noticeable on dark skin; if you notice it, tell your doctor.
• Asthma: Worsening of asthma has been reported with azelaic acid use. If you have asthma, ask your doctor before use.

If severe redness, flaking, itching or burning develops, stop the product and consult your doctor. In comparative studies, side effects were found to be similar to other treatments, but these studies cannot predict your individual reaction.

Is it used together with other agents?

Direct data on combinations is limited. Therefore the recommendations are mostly based on general tolerance logic.

• Glycolic acid and salicylic acid: Combining them on the same evening may increase dryness. Separate them onto different days; do not use them together at the start.
• Retinol: Instead of applying them in the same layer, choose different evenings; if you have just started, get used to one first.
• Benzoyl peroxide: A review on acne in pregnancy mentions that they may be used together, but leave this decision to your doctor.
• Niacinamide and hyaluronic acid: Generally pairings that do not strain the skin, but still add new products one at a time so that if a reaction occurs you can identify its source.

What to expect and when?

The durations below come from data on drug forms. Cosmetic low concentrations may not fit this schedule, and there is no separate schedule data for those concentrations.

Azelaic acid or another agent?

Three questions about azelaic acid

Does it help acne scars?

It may help reduce the look of dark spots left after acne, and this use stands out especially on dark skin. It is not expected to correct pitted scars. Options are in the acne scar article.

Can it be bought without a prescription?

Low-concentration cosmetic products can be bought. The sales conditions of 15% and 20% forms vary by country; ask your pharmacist. Being able to buy it does not mean self-treatment is appropriate.

Does it cause sun sensitivity?

No clear sun sensitivity data stands out as it does with AHAs. Even so, if you are targeting spots or the skin has become irritated, sun protection is essential, because sun can darken the spot again.

Pregnancy and breastfeeding

Azelaic acid is one of the frequently mentioned options for acne in pregnancy. Absorption from a cream applied to the skin is reported at about 4%; no birth defects were seen in animal studies, but embryo harm has been reported at high oral doses. There are no controlled studies in pregnant women. So while some sources consider it safe, the drug label says 'only if clearly needed', and a review recommends use on a small area and preferably excluding the first three months.

Conclusion: If you are pregnant or breastfeeding, do not start on your own; ask your doctor. During breastfeeding, it is recommended not to apply it to the breast and to areas the baby will contact.

When not to handle it yourself?

• If there is persistent redness, visible veins and stinging: It may be rosacea; the doctor makes the diagnosis. The wrong product can worsen the picture.
• If there are symmetrical, spreading brown spots on the cheeks and forehead: It may be melasma. Sun protection and doctor follow-up are essential.
• If there is recurring acne along the jawline: The hormonal acne article explains when to see a doctor.
• If there is deep acne or noticeable scarring: Do not waste time on over-the-counter products.
• If the shape, color or border of a spot changes: Get an examination immediately; do not wait by applying a product to it.