Ingredient · Alpha-hydroxy Acid · Mandelic
P. 11 · BRIEFThe largest alpha-hydroxy acid in cosmetic use. Slow-penetrating, mild, and uniquely friendly to deeper skin tones where post-inflammatory pigment is the real risk of any acid. The right tool for sensitive, reactive, or melanin-rich skin — and an underrated one for early acne in those same groups.
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Mandelic acid is derived from bitter almonds and is, by molecular weight, the largest AHA in routine use — roughly twice the size of lactic and three times the size of glycolic. Bigger molecule means slower diffusion through the stratum corneum, which means a flatter irritation curve, which is the entire point. Mandelic produces gentler, more uniform exfoliation with a meaningfully lower risk of post-inflammatory hyperpigmentation in deeper skin tones.
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On exfoliation
Loosens corneocyte adhesion at the surface. Slowest of the AHAs by depth.
On bacteria
Mild antibacterial activity, including against C. acnes — useful in acne-prone skin.
On pigment
Tyrosinase inhibition at higher concentrations. Particularly useful for melasma in skin of colour.
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Nightly. The default for sensitive skin.
Effective, still tolerable. Sweet spot for most.
Mandelic + 1% SA for oily, acne-prone, easily-pigmented skin.
In-office only. Lowest PIH risk among acid peels.
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— § 07
Beginner-friendly, sensitive-skin standard. Gentle vehicle.
Cheapest credible 10%. Honest dose, simple vehicle.
Higher concentration, clean formulation. For experienced users.
Premium pigment-targeted blend. Good for mid-tone PIH.
— § 08
Mandelic if you have sensitive, reactive, or deeper-pigmented skin — particularly Fitzpatrick IV–VI, where glycolic's PIH risk is real. Glycolic if you have established tolerance and want maximum exfoliation.
For mild comedonal and inflammatory acne, often yes. For moderate-to-severe, it is an adjunct — not a replacement for adapalene or BPO.
Yes, at 5–10%. The forgiving curve is exactly the point. Daily nightly use is the norm, not the exception.
Lower-volume production and patent-protected delivery systems in some premium products. The molecule itself is not exotic.
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— Cross-references
Concerns it treats