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Sodium Cocoyl Isethionate
Sodium Cocoyl Isethionate
Solid-bar-friendly surfactant. Produces a creamy lather without the barrier strip of sulfates.
What it does
Sodium cocoyl isethionate is the workhorse surfactant in syndet bars and many gentle foaming face cleansers. It's anionic but considerably milder than SLS, with a creamier lather. SCI is one of the more common 'this cleanser is gentle but actually foams' picks; it's the surfactant behind several drugstore bars marketed for sensitive skin.
The evidence, graded
moderateCommon sensitivity and contact-allergy triggers in skincare include fragrance (the most-cited cosmetic allergen), essential oils, denatured alcohol, and certain preservatives (methylisothiazolinone, formaldehyde-releasers). Patch test new products on the inner forearm for 48–72 hours before face-wide use.Warshaw 2020 · Dermatitis ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
sci
Pairs worth knowing
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