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Sa

Salicylic Acid

Salicylic AcidExfoliant

Oil-soluble beta hydroxy acid. Penetrates pores and clears clogs — go-to for blackheads and oily skin.

What it does

Salicylic acid is lipid-soluble, so it dissolves the sebum + dead-cell mix that plugs pores. Effective for comedonal acne, blackheads, and oily skin. OTC products top out at 2%; medical peels go higher.

The evidence, graded

expert consensusRetinol and a BHA — salicylic acid, or its ester betaine salicylate — can be layered for some users without issue, but the combination raises dryness and barrier risk. Start with alternate nights and merge only if tolerated.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 consensusTopical salicylic acid at 2% or below is generally considered safe in pregnancy when used on small areas. Higher concentrations, large-area or under-occlusion use, and oral salicylates should be avoided.Bozzo 2011 · Canadian Family Physician

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

Also known as

bha, capryloyl salicylic acid

Pairs worth knowing

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