Am
Ammonium Lauryl Sulfate
Ammonium Lauryl Sulfate
Sulfate surfactant similar to SLS. Cleans hard; not the gentlest pick for a dry-skin face cleanser.
What it does
Ammonium lauryl sulfate is functionally very close to SLS — both are short-chain alkyl sulfates with strong defatting properties. ALS shows up most often in shampoos and the occasional foaming cleanser. The use case is identical to SLS: powerful cleansing that rinses clean, with a higher chance of barrier dryness if used on the face daily.
The evidence, graded
expert consensusDuring an active eczema flare, most actives (retinoids, AHAs, BHAs, vitamin C) can worsen barrier dysfunction and prolong the flare. Focus on barrier repair until the skin is calm; consult a derm if flares are recurrent.Eichenfield 2014 · Journal of the American Academy of Dermatology ↗
expert consensusIf skin is reactive, peeling, stinging, or burning unexpectedly, pause all actives and rebuild the barrier with simple cleanser, ceramide-rich moisturizer, and SPF for 2–4 weeks before re-introducing actives one at a time.Lodén 2003 · American Journal of Clinical Dermatology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
als
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