Azelaic Acid is a naturally occurring 9-carbon dicarboxylic acid (MW 188.22 Da) found in grains like wheat, barley, and rye — and also produced by the yeast Malassezia furfur on human skin. It is a well-tolerated active with a strong safety profile, with demonstrated anti-inflammatory, antibacterial, anti-keratinising, and tyrosinase-inhibiting (brightening) properties. The CIR Expert Panel classifies it as "Safe as Used" — the most favorable CIR conclusion, indicating no restrictions needed. Available as both OTC cosmetic (10%) and prescription medication (15–20% for acne and rosacea, e.g., Finacea, Skinoren). Unlike AHAs, azelaic acid does not intrinsically increase UV sensitivity, though sunscreen remains essential. Registered as EU CosIng #74538. No harmonised GHS classification under CLP Annex VI. Mild transient irritation (burning, stinging) is common during initial use at higher concentrations. Found in 563 products.
Azelaic Acid (INCI: AZELAIC ACID, CAS 123-99-9) is a naturally occurring saturated 9-carbon dicarboxylic acid with the molecular formula C₉H₁₆O₄ and a molecular weight of 188.22 Da. It is found in grains such as wheat, barley, and rye, and is also produced by the commensal yeast Malassezia furfur (formerly Pityrosporum ovale) on human skin as a byproduct of lipid metabolism. It is registered in the EU CosIng database (#74538) with functions as a skin conditioning agent, exfoliant, pH adjuster, and fragrance ingredient. The CIR Expert Panel has assessed azelaic acid and concluded it is "Safe as Used" — the most favorable CIR conclusion, indicating no restrictions are needed at current use concentrations.
Azelaic acid occupies a unique position in dermatology as both a cosmetic ingredient and a prescription medication. At OTC cosmetic concentrations (typically 10%), it provides gentle exfoliation, brightening, and anti-inflammatory benefits. At prescription strengths (15% gel for rosacea, 20% cream for acne), it is a well-established treatment for papulopustular rosacea, moderate acne vulgaris, and post-inflammatory hyperpigmentation (PIH). Its mechanism of action is multi-pronged: it inhibits tyrosinase (reducing melanin production for brightening), has direct antibacterial activity against Cutibacterium acnes (the bacterium involved in acne), normalises keratinisation (preventing pore clogging), and has anti-inflammatory properties that reduce redness and swelling. Our database identifies azelaic acid in 563 products.
One of azelaic acid's notable advantages is what it does NOT do: unlike AHAs (glycolic acid, lactic acid, mandelic acid), azelaic acid does not intrinsically increase UV sensitivity. It does not cause aggressive stratum corneum thinning like AHAs, though it does modulate keratinisation as part of its therapeutic mechanism. This allows morning use without intrinsic photosensitivity concerns — though daily sunscreen remains essential, especially when treating hyperpigmentation. Azelaic acid has no harmonised GHS classification under CLP Annex VI (though supplier safety data sheets may list irritant classifications at full concentration), low sensitisation risk, and zero conflicts in our database. It is commonly used by dermatologists during pregnancy as a lower-risk alternative to retinoids and hydroquinone, though pregnancy-specific clinical trial data remains limited. No SCCS individual opinion exists for azelaic acid, but this does not affect the safety assessment given the CIR "Safe as Used" conclusion. Note: mild transient irritation (burning, stinging, itching) is common during initial use, particularly at prescription concentrations (15–20%) — this typically resolves within 2–4 weeks.
Azelaic acid has direct antibacterial activity against Cutibacterium acnes — the bacterium central to acne pathogenesis. It also normalises keratinisation, preventing the formation of microcomedones (clogged pores). Clinical trials demonstrate that 20% azelaic acid cream is comparable in efficacy to benzoyl peroxide, tretinoin, and oral tetracycline for mild-to-moderate acne, with fewer side effects. It reduces both inflammatory (papules, pustules) and non-inflammatory (comedones) acne lesions. Available as 20% prescription cream (e.g., Skinoren) and 10% OTC formulations.
Azelaic acid inhibits tyrosinase — the enzyme responsible for melanin production — selectively in hyperactive melanocytes without affecting normally pigmented skin. This makes it effective for treating post-inflammatory hyperpigmentation (PIH), melasma, and uneven skin tone, particularly in darker skin tones (Fitzpatrick IV–VI) where aggressive treatments can paradoxically worsen pigmentation. Unlike hydroquinone, azelaic acid does not cause ochronosis (paradoxical darkening) and is considered safe for long-term use.
Azelaic acid is one of the most well-established treatments for papulopustular rosacea. At 15% gel (prescription, e.g., Finacea), it significantly reduces inflammatory papules, pustules, and erythema (redness) associated with rosacea. Its anti-inflammatory mechanism includes inhibition of reactive oxygen species (ROS) production and modulation of the kallikrein-cathelicidin innate immune pathway — a key driver of rosacea inflammation. It is recommended as a first-line treatment in multiple rosacea clinical guidelines.
As a dicarboxylic acid, azelaic acid provides gentle exfoliation by normalising the desquamation (shedding) process of the stratum corneum. Unlike AHAs, this exfoliation does not intrinsically increase UV sensitivity and does not cause aggressive stratum corneum thinning — though it does modulate keratinisation as part of its therapeutic action. The result is smoother skin texture, refined pores, and improved overall skin clarity. Azelaic acid's exfoliating action is milder than glycolic acid or salicylic acid, making it suitable for skin types that cannot tolerate stronger chemical exfoliants.
Suitable for: All skin types, including sensitive, acne-prone, rosacea-prone, and darker skin tones. Commonly used during pregnancy as a lower-risk alternative (though pregnancy-specific trial data is limited — consult your doctor). Particularly well-suited for those who find AHAs, retinoids, or benzoyl peroxide too irritating. Can be used morning and evening — does not intrinsically increase UV sensitivity. Mild transient irritation is common during initial use.
Azelaic Acid carries a SkinSenseDiary safety rating of 2/10 — low risk. The CIR Expert Panel classifies it as "Safe as Used" — the most favorable CIR conclusion, indicating no restrictions are needed at current use concentrations. Azelaic acid has no harmonised GHS classification under CLP Annex VI, low sensitisation risk, and zero conflicts in our database. It is naturally produced by the body and occurs in common grains. It is also a well-established prescription medication (15–20%) with decades of clinical use. Unlike AHAs, it does not intrinsically increase UV sensitivity. A well-tolerated active with a strong safety profile — though mild transient irritation (burning, stinging, itching) is common during initial use, particularly at prescription concentrations.
Initial tingling is normal and temporary: When starting azelaic acid — especially at 15–20% prescription strength — mild stinging, tingling, or burning may occur for the first 2–4 weeks. This is a common irritant response, not an allergic reaction, and typically resolves as the skin adjusts. If irritation is persistent or severe, reduce frequency or try a lower concentration. Applying azelaic acid to slightly damp skin can increase tingling; applying to fully dry skin reduces it.
Does not intrinsically increase UV sensitivity: Unlike AHAs (glycolic acid, lactic acid, mandelic acid) and retinoids, azelaic acid does not intrinsically increase skin sensitivity to UV radiation. It can be used in the morning without the photosensitivity concerns associated with AHAs. However, daily broad-spectrum SPF 30+ sunscreen remains essential — particularly if you are treating hyperpigmentation or acne, since UV exposure drives pigmentation recurrence and can worsen post-inflammatory marks.
OTC vs prescription strength: OTC azelaic acid products contain up to 10% and are suitable for mild acne, uneven skin tone, and general skin maintenance. Prescription formulations (15% gel for rosacea, 20% cream for acne) deliver stronger clinical results and are recommended for moderate-to-severe acne, rosacea, or stubborn hyperpigmentation. If 10% OTC is insufficient after 8–12 weeks of consistent use, consult a dermatologist about prescription options.
Naturally occurring and well-studied: Azelaic acid is not a synthetic chemical unfamiliar to the body — it is a normal intermediate in fatty acid metabolism, present in the human body and in common dietary grains. It has decades of clinical use as both a cosmetic ingredient and a prescription medication, with an extensive body of safety data supporting its use.
Azelaic acid is considered low risk and commonly used during pregnancy, though pregnancy-specific clinical trial data remains limited. It has no harmonised GHS classification under CLP Annex VI — including no reproductive or developmental toxicity codes (no H361d, no H362). The CIR Expert Panel classifies it as "Safe as Used." Azelaic acid is a naturally occurring substance in the human body (intermediate in fatty acid metabolism) and in common grains, and systemic absorption from topical application is minimal. Many dermatologists recommend azelaic acid as a lower-risk alternative to retinoids (Category X), hydroquinone, and high-concentration salicylic acid for treating acne and hyperpigmentation during pregnancy. It is classified as FDA Pregnancy Category B (no evidence of risk in animal studies, but no adequate controlled human studies). Both OTC (10%) and prescription (15–20%) concentrations are commonly used during pregnancy under medical guidance, but the evidence base is primarily observational rather than from controlled trials. Consult your healthcare provider for individualised advice.
Start with a gentle, pH-balanced cleanser. Pat skin completely dry before applying azelaic acid — applying to damp skin can increase tingling and stinging. Azelaic acid works best on clean, dry skin.
Apply a thin layer of azelaic acid product to the affected areas. Unlike AHAs and retinoids, azelaic acid does not intrinsically increase UV sensitivity, so it can be used in the morning, evening, or both. Start with once daily application for the first 2 weeks, then increase to twice daily if tolerated. A pea-sized amount is sufficient for the full face. Avoid the eye area and mucous membranes.
Allow azelaic acid to absorb for 5–10 minutes, then follow with a hydrating moisturiser. Although azelaic acid does not intrinsically increase UV sensitivity, daily broad-spectrum SPF 30+ sunscreen is recommended — especially if treating hyperpigmentation, as UV exposure drives pigmentation recurrence. Some users find azelaic acid mildly drying at higher concentrations; a ceramide-rich moisturiser can offset this.
Azelaic acid works gradually. Visible improvements in acne typically appear at 4–8 weeks. Hyperpigmentation improvement may take 8–12 weeks or longer. Rosacea improvement with prescription 15% gel is usually seen within 4–8 weeks. Consistency is key — azelaic acid is most effective with regular, sustained use. If initial tingling occurs, it usually subsides within 2–4 weeks. Do not discontinue prematurely due to temporary irritation.
Lightweight leave-on format, typically 10% azelaic acid. Easiest to layer with other products. Most popular OTC format. Apply after cleansing, before moisturiser. Use once or twice daily.
Prescription formulations: 15% gel (Finacea) for rosacea, 20% cream (Skinoren) for acne. Thicker texture, stronger clinical results. Applied as directed by prescribing dermatologist, typically twice daily.
Combined formulations pairing azelaic acid with niacinamide, salicylic acid, or hyaluronic acid. Lower individual concentrations (5–10% azelaic acid) but synergistic benefits. Good for maintenance routines.
An excellent pairing — arguably the best combination partner for azelaic acid. Niacinamide strengthens the skin barrier, regulates sebum, and has its own anti-inflammatory and brightening effects. Both ingredients are well-tolerated and neither increases UV sensitivity. Can be used in the same routine, same step.
Hydrating ingredients complement azelaic acid's active effects. Azelaic acid can be mildly drying at higher concentrations, and hyaluronic acid and ceramide-rich moisturisers help maintain hydration and barrier function. Apply azelaic acid first, then layer hydrating products.
Although azelaic acid does not intrinsically increase UV sensitivity (unlike AHAs), daily SPF 30+ is still recommended — especially when treating hyperpigmentation, as UV exposure is the primary driver of pigmentation recurrence. Azelaic acid + sunscreen is a powerful anti-pigmentation duo.
Both are active ingredients that can cause initial irritation. At prescription strength (azelaic acid 15–20% + tretinoin), this combination should only be used under dermatological supervision. At OTC strength (azelaic acid 10% + retinol 0.3–0.5%), many people tolerate them together, but introduce one at a time. Consider azelaic acid in the morning and retinol in the evening if both cause tingling.
Combining azelaic acid with other exfoliating acids can increase the risk of irritation and dryness. Azelaic acid is milder than most AHAs, but stacking exfoliants is generally unnecessary and can compromise the skin barrier. If using both, alternate days or apply them at different times (e.g., AHA in the evening, azelaic acid in the morning).
Both have antibacterial properties and can treat acne. Using them together may be drying and irritating — particularly for sensitive skin. In clinical settings, dermatologists sometimes combine them for severe acne, but this should be done under supervision. If combining at home, apply at different times of day and monitor for excessive dryness.
Found in 563 products in our database. Here are some well-known azelaic acid options across OTC and prescription categories. Note: formulations change — always check the current INCI list on the product packaging or label.
Use the SkinSenseDiary app to scan product barcodes, check ingredient safety ratings, and get personalized skincare recommendations.
Join the Waitlist