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Azelaic Acid

Azelaic Acid is a active, antioxidant, antimicrobial used in cosmetic and personal-care formulation. Typical use level is 5%–20%. It is oil-soluble. Stable in the pH 3.5–5.5 range.

At a glance

CAS number
123-99-9
INCI name
Azelaic Acid
Function
active, antioxidant, antimicrobial
Typical use level
5%–20%
Solubility
oil
Stable pH
3.5–5.5

CAS number and synonyms are sourced from PubChem. Function, usage levels, pH and compatibility are AI-assisted formulation guidance — verify against your supplier's technical data sheet and applicable regulations before use.

Also known as

azelaic acid Finacea Anchoic acid Lepargylic acid 1,7-Heptanedicarboxylic acid Azelex Skinoren Heptanedicarboxylic acid 1,9-Nonanedioic acid Emerox 1110 Emerox 1144 n-Nonanedioic acid

Compatibility

Works well with:
Niacinamide Zinc PCA Salicylic Acid Glycerin Allantoin Panthenol Ceramides Hyaluronic Acid Retinol

Use caution with:
High pH bases Strongly alkaline buffers Triethanolamine (high concentrations)

Azelaic acid requires a low pH environment (3.5–5.5) for stability and efficacy; strongly alkaline ingredients can form azelaic acid salts, reducing activity. It is poorly water-soluble and typically requires propylene glycol, PPG, or other solubilizers to disperse uniformly in aqueous formulas. Combinations with other keratolytic actives like salicylic acid or retinol can enhance efficacy but may increase irritation risk.

Formulation notes

Azelaic acid is a prescription-strength active at 15–20% (e.g., Finacea, Skinoren) for acne and rosacea; OTC cosmetic use is typically 5–10%. Poor solubility requires careful formulation; often used as a micronized suspension or dissolved in glycols. Generally well tolerated but may cause transient tingling or erythema. No specific EU/US leave-on concentration restriction as a cosmetic, but efficacy is concentration-dependent.

Frequently asked questions

What is Azelaic Acid?

Azelaic Acid is a active, antioxidant, antimicrobial used in cosmetic and personal-care formulation. Typical use level is 5%–20%. It is oil-soluble. Stable in the pH 3.5–5.5 range.

What is Azelaic Acid used for?

Azelaic Acid is used as active, antioxidant, antimicrobial in cosmetic and personal-care formulations.

What is the typical use level of Azelaic Acid?

Azelaic Acid is typically used at 5%–20% in the finished formulation. Always confirm against your supplier's technical data sheet.

What is the CAS number of Azelaic Acid?

The CAS registry number for Azelaic Acid is 123-99-9. Its INCI name is Azelaic Acid.

At what pH is Azelaic Acid stable?

Azelaic Acid is generally stable in the pH 3.5–5.5 range.

What ingredients are compatible with Azelaic Acid?

Azelaic Acid works well with Niacinamide, Zinc PCA, Salicylic Acid, Glycerin, Allantoin, Panthenol, Ceramides, Hyaluronic Acid, Retinol. Use caution when combining it with High pH bases, Strongly alkaline buffers, Triethanolamine (high concentrations).

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