Azelaic Acid: Evidence-Based Benefits for Hyperpigmentation, Acne, and Uneven Skin Tone
Why azelaic acid is so important in modern formulations:
Azelaic acid is a proven active ingredient for cosmetic leave-on products targeting hyperpigmentation, post-inflammatory hyperpigmentation (PIH), uneven skin tone, acne, and inflammation-related redness. It is frequently chosen because it strikes a good balance between efficacy and tolerability—especially for sensitive and melanin-rich skin.
Brief definition: Azealic acid refers to a product containing 10% azelaic acid as the active ingredient (typically a serum, gel-cream, or emulsion) that helps achieve a more even skin tone and a smoother complexion.
The Effects of Azelaic Acid
The effects are based on several mechanisms acting in parallel
- Tyrosinase inhibition: Reduces a key step in melanin formation and is therefore important for treating pigment spots and melasma.
- Selectivity in hyperpigmentation: Azelaic acid acts preferentially where pigment activity is elevated, rather than lightening the skin “across the board.”
- Inflammation modulation: Helpful for PIH (e.g., post-acne), as inflammation remains a trigger for pigmentation.
- Antimicrobial effect and support for blemishes: Relevant for acne-prone skin (since less inflammation often means fewer pigment residues).
In practice, azelaic acid is therefore often used as a “multitool”: not just for spots, but for the overall complexion.
The evidence base shows what efficacy tests and clinical studies confirm
Clinical data confirm the benefits of azelaic acid, particularly for melasma/hyperpigmentation and acne-related pigment changes.
- In a large, double-blind study over 24 weeks, 20% azelaic acid showed comparable clinical results to 4% hydroquinone for melasma (with accompanying sun protection).
- Further clinical data support its efficacy for hyperpigmentation in darker skin types (azelaic acid vs. placebo).
- For melasma, a double-blind comparative study showed significant improvements in pigment intensity and lesion size.
- For acne-associated redness and pigment changes (PIE/PIH), recent clinical results are available for a gel containing 15% azelaic acid.
- In a comparative study, 20% azelaic acid was also described as effective for acne-related PIH.
Classification for cosmetics: Even though not every study tests exactly 10%, these data support the dermatological relevance of the active ingredient and explain why azelaic acid is established as a well-tolerated, effective standard in the cosmetic sector.
Application in Product Formulations
Azelaic acid is particularly suitable for:
- Serums/gel serums (targeted at spots, PIH, uneven texture),
- Gel creams/emulsions (daily routine for an even skin tone),
- Combination care for acne and pigment spots (when inflammation and residual spots occur together).
Tip from formulation practice: For sensitive skin, azelaic acid is often combined with barrier-strengthening and soothing ingredients (e.g., moisturizing factors, lipid systems, panthenol-like formulations) to facilitate daily use.
Note for brands: We can also develop formulations with up to 20% azelaic acid—with realistic sensory expectations
If a brand aims for a higher active ingredient concentration, we can develop formulations with up to 20% azelaic acid. It is important to have technically accurate expectations: azelaic acid is not fully soluble, which is why higher dosages are often implemented as a suspension in practice. This can be noticeable sensorily as a slight peeling or “powdery” sensation—depending on particle management and the system. This is precisely where the difference lies between “works somehow” and “works in a market-ready way”: We have the formulation expertise to balance particle distribution, stability, skin feel, and performance in such a way that the product performs convincingly on the market.
Mini-FAQ
What is azelaic acid suitable for?
For hyperpigmentation, PIH, uneven skin tone, acne-related skin irritation, and often also for sensitive skin.
How does azelaic acid work against pigment spots?
Through tyrosinase inhibition, anti-inflammatory effects, and a selective action on areas with increased pigment activity.
Can concentrations exceed 10%?
Yes, up to 20% is possible, typically as a suspension with a slightly noticeable particle/exfoliating sensation.
New products with azelaic acid for your brand
For a quick market entry, Tojo Cosmetics offers immediately available, EU-compliant white label products in which this active ingredient is already formulated.
For individual production orders, Cosactive offers formulation-tested active ingredient mixtures starting from small quantities.
At our partner company Cosmacon, we are happy to assist you with individual product developments using this innovative active ingredient.
Just ask us!
References:
Clinical studies on the efficacy of azelaic acid
- 20% azelaic acid vs. 4% hydroquinone for melasma (24 weeks, double-blind, n=329)
- A double-blind comparison of 20% azelaic acid cream and 4% hydroquinone cream in the treatment of melasma.
- https://pubmed.ncbi.nlm.nih.gov/1816137/
- Azelaic acid for melasma – clinical efficacy and tolerability
- Breathnach AS. Melanin hyperpigmentation of the skin: melasma, topical treatment with azelaic acid, and other therapies.
- https://pubmed.ncbi.nlm.nih.gov/8654129/
- Double-blind comparative study: azelaic acid vs. hydroquinone for melasma
- A comparative study of azelaic acid and hydroquinone in the treatment of melasma.
- https://pubmed.ncbi.nlm.nih.gov/2528260/
- 15% azelaic acid gel for acne-induced post-inflammatory erythema/pigmentation (PIE/PIH)
- Clinical evaluation of azelaic acid 15% gel in post-acne erythema and pigmentation.
- https://pubmed.ncbi.nlm.nih.gov/38734843/
- 20% azelaic acid for acne-related post-inflammatory hyperpigmentation
- Azelaic acid versus tranexamic acid in post-inflammatory hyperpigmentation secondary to acne vulgaris.
- https://pubmed.ncbi.nlm.nih.gov/37213446/