Az
Azelaic Acid
Azelaic AcidActive
Multitasker for redness, post-acne marks, and rosacea. Pregnancy-friendly active.
What it does
Azelaic acid is a dicarboxylic acid produced by skin yeast. Antibacterial (helpful for acne), inhibits tyrosinase (brightening), and reduces inflammation (rosacea, redness). One of the few actives considered safe during pregnancy. OTC formulations typically 10%; prescription versions go to 15–20%.
The evidence, graded
expert consensusAzelaic acid and retinol generally pair well. Azelaic acid's anti-inflammatory effect can offset retinoid irritation, and the two are commonly stacked for acne and post-inflammatory pigmentation.Sieber 2014 · Skin Pharmacology and Physiology ↗
expert consensusHydroquinone is absorbed through skin at 35–45% — much higher than most topicals. Pregnancy and breastfeeding guidance is to avoid it, even though existing studies have not shown harm.Bozzo 2011 · Canadian Family Physician ↗
expert consensusAzelaic acid shows reduced redness and pigmentation in 4–8 weeks. Acne and rosacea benefits accumulate over 8–12 weeks. Tolerance is good for most users including pregnancy and rosacea.Sieber 2014 · Skin Pharmacology and Physiology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Pairs worth knowing
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