Reviewed by the HyaluFlow Health Editorial Team | Published: October 11, 2026 | Last Updated: October 11, 2026

Quick Answer: Azelaic acid is a gentle, multi-purpose skincare acid with clinical support for rosacea, acne and some types of dark marks. Over-the-counter products go up to 10%, while the strengths used in most trials, 15% and 20%, are prescription. It works slowly, so expect months rather than days.

Key Takeaways

  • Azelaic acid has four documented actions: it is antibacterial, anti-inflammatory, antioxidant and it slows pigment production.
  • The strongest trial evidence is for papulopustular rosacea; acne and melasma evidence is good but more mixed.
  • Strength matters: most clinical trials used 15% gel or 20% cream, which is more than most store-bought serums contain.
  • Side effects are usually mild stinging, itching or dryness in the first weeks.
  • Topical azelaic acid is generally considered safe in pregnancy, but check with your doctor.

What Is Azelaic Acid?

Azelaic acid is a naturally occurring nine-carbon dicarboxylic acid, produced by the skin yeast Malassezia. It has been used in dermatology for years, and a 15% gel was FDA-approved for papulopustular rosacea in 2002. It is a milder acid than salicylic acid or adapalene, which is why it is often suggested for skin that cannot tolerate stronger actives.

How Does Azelaic Acid Work?

A 2025 review of its pharmacology describes four main actions:

  • Antibacterial: it reduces Cutibacterium acnes and other bacteria on the skin, with a lower reported risk of resistance than antibiotics.
  • Anti-inflammatory: it lowers inflammatory signals involved in acne and rosacea.
  • Pigment-slowing: it reversibly inhibits tyrosinase, the enzyme that drives melanin production.
  • Antioxidant: it reduces oxidative stress in inflamed skin.

What Does the Evidence Say?

Rosacea: the strongest evidence

Two double-blind, randomised phase III trials enrolled 664 people with moderate papulopustular rosacea and compared 15% azelaic acid gel with a vehicle gel (the same base without the active ingredient), applied twice daily. Inflammatory lesions fell by 58% versus 40% in the first trial and 51% versus 39% in the second. Redness improved in 44% versus 29% and 46% versus 28% of participants, and no serious treatment-related adverse events were reported. Reviews also describe it performing comparably to, or in some trials better than, metronidazole gel.

Acne: helpful, usually as part of a plan

Reviews report that 15% gel produced lesion reductions comparable to adapalene 0.1% with less irritation, and that 20% cream reduced lesions with fewer local side effects than tretinoin 0.05%. It treats both inflamed and non-inflamed (clogged pore) acne. A 2024 review calls it a common second-line option and notes it was less effective than benzoyl peroxide/clindamycin or combined oral contraceptives in some comparisons. Dermatologists quoted by NBC News add that it works best on marks left after acne and is not a fix for deep cystic acne.

Dark spots and melasma: comparable to hydroquinone in some studies

A 24-week study of 20% cream in people with Fitzpatrick skin types IV to VI reported improved facial hyperpigmentation. A 24-month trial comparing 20% azelaic acid with 4% hydroquinone found no significant difference in overall melasma improvement, though other studies are mixed, with hydroquinone sometimes working better and azelaic acid being better tolerated. Combining it with tretinoin has been reported to speed visible lightening. Melasma is an off-label use in Europe. Hyperpigmentation also needs daily sunscreen, since UV can undo progress.

Other conditions

Researchers have looked at psoriasis, alopecia areata and folliculitis, but the evidence for these is limited.

What Strength Do You Need?

  • Over the counter: up to 10%. Cosmetic products are often lower and blended with other ingredients.
  • Prescription: 15% gel or foam and 20% cream, the concentrations with the most clinical research behind them.
  • Formulation counts: azelaic acid dissolves poorly in water and penetrates skin slowly, so the delivery system affects how well a product works, not just the percentage on the label.

For rosacea or stubborn pigmentation, ask a dermatologist whether a prescription strength is worth it.

How to Use Azelaic Acid

  1. Cleanse and dry skin.
  2. Start once a day, at night. If your skin tolerates it for a few weeks, move to twice daily.
  3. Apply a thin layer to the whole affected area rather than only spots.
  4. Follow with a moisturiser if your skin feels tight.
  5. Wear sunscreen every morning.

Avoid layering it with strong exfoliating acids such as AHAs and BHAs at first, which can add irritation. Introduce one active at a time rather than combining several potentially irritating ingredients at once.

How Long Does It Take to Work?

Be patient. Dermatologists quoted by NBC News say prescription strengths may show improvement in about six weeks to three months, and over-the-counter products in roughly three to four months. Brightening can take six months to a year and may be modest. One dermatologist notes that the most common complaint is that it does not work well enough, which is a reason to set realistic expectations and use the right strength.

Side Effects and Safety

  • Common: burning, stinging, itching, redness, dryness and scaling. These are usually mild, temporary and most noticeable in the first few weeks.
  • Uncommon: contact dermatitis, facial swelling and acne flare-ups were reported in fewer than 1% of patients and generally cleared when treatment stopped.
  • Whole-body effects: very rare, because little passes through the skin.
  • Very sensitive skin: stinging or burning is more likely, and a rash can worsen hyperpigmentation, so stop and seek advice if irritation persists.

Is Azelaic Acid Safe in Pregnancy?

Reviews describe topical azelaic acid as considered safe during pregnancy, and a 2024 review lists it as pregnancy category B for topical use. It is often highlighted as one of the few acne options suitable for pregnancy. Dermatologists quoted by NBC News also describe it as an option while breastfeeding. Even so, check with your doctor or pharmacist before starting any new treatment.

Who Is It Best For?

  • People with rosacea-prone redness and bumps
  • Mild to moderate acne with lingering dark marks
  • Sensitive skin that cannot handle stronger actives
  • People who are pregnant or breastfeeding, after medical advice
  • Darker skin with post-acne marks: one 24-week study covered Fitzpatrick types IV to VI, and daily sunscreen is essential

Evidence Strength Summary

  • Improves papulopustular rosacea: strong, supported by large randomised trials.
  • Improves mild to moderate acne: moderate, comparable to some standard treatments but often used as a second-line option.
  • Improves melasma and dark marks: moderate, with mixed results compared with hydroquinone.
  • Effective for other conditions: limited.
  • Safe in pregnancy: supported by reviews, but confirm with a doctor.

Bottom Line

Azelaic acid is a well-researched, gentle active that earns its place for rosacea, acne marks and pigmentation. It is not fast, and the strength you choose matters. Start slowly, use sunscreen daily, give it at least three months, and see a dermatologist if you want prescription strength or your skin does not improve.

This article is for educational purposes and is not medical advice. Speak with a qualified healthcare professional about any skin condition, especially during pregnancy.

Sources

  • A Comprehensive Review of Azelaic Acid Pharmacological Properties, Clinical Applications, and Innovative Topical Formulations. Pharmaceuticals (2025). MDPI
  • Feng et al. (2024). Review of azelaic acid in dermatology. Clinical, Cosmetic and Investigational Dermatology. PMC
  • Two phase III trials of 15% azelaic acid gel in papulopustular rosacea (664 patients). PubMed
  • Acne and Pregnancy: A Clinical Review and Practice Pearls. Cutis. MDedge
  • NBC Select: 11 Best Azelaic Acid Products, According to Derms. NBC News