Cited skincare — every flag names its source, no upsell.
La

Lactic Acid

Lactic AcidExfoliant

Larger AHA than glycolic. Gentler, also acts as a humectant.

What it does

Lactic acid exfoliates more gently than glycolic and pulls water into the skin, making it a friendlier choice for sensitive skin. Higher percentages (10%+) approach glycolic's intensity.

The evidence, graded

expert consensusRetinol and AHAs (glycolic, lactic) can both irritate skin when layered in the same routine. Most people do better alternating them on different nights.Mukherjee 2006 · Clinical Interventions in Aging ↗
expert consensusTretinoin is significantly more potent than retinol; combining it with AHAs in the same routine raises irritation risk substantially.Mukherjee 2006 · Clinical Interventions in Aging ↗
expert consensusAHAs and BHAs can be combined safely in well-formulated products. The 'never mix them' rule is overstated — the real concern is total acid load on the skin barrier, not the chemistry of mixing them.Kornhauser 2010 · Clinical and Cosmetic Investigative Dermatology ↗
expert consensusLactic acid is gentler than glycolic but still raises retinoid irritation when stacked in the same routine.Smith 1996 · Journal of the American Academy of Dermatology ↗

Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.

Pairs worth knowing

Niacinamide (Vitamin B3) · works together ↗Panthenol (Pro-vitamin B5) · works together ↗Retinol · worth separating ↗Tretinoin · worth separating ↗

Read more

How Drop works · 5 minConcentration Alone Doesn't Tell the Whole Story: pH, Formulation, and Delivery MatterA higher vitamin C percentage isn't always a more potent serum. Concentration is one variable; pH, formulation, and delivery often matter as much or more.

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