Sodium Cocoamphoacetate

Sodium cocoamphoacetate is an amphoteric surfactant used in cleansers (often a few to ~10%+ actives) and is generally milder than anionic sulfates, but it is still a surfactant that can disrupt barrier lipids and increase stinging in compromised skin. Clinical and patch-test experience shows low-to-moderate irritation potential overall, with higher risk in eczema, post-procedure, or very reactive individuals—especially with frequent use or in combination with other detergents. For patient safety, I rate it as mild because irritation is plausible in sensitive populations even when marketed as “gentle.” Safety Notes: In commercial rinse-off products (facial cleansers, baby washes, micellar/foaming waters, sulfate-free shampoos), sodium cocoamphoacetate is often used at low levels (~0.2–2%) as a secondary amphoteric surfactant for mildness/viscosity and foam boosting alongside other surfactants. High-strength consumer-available formulations (very mild “surfactant-only” cleansing gels/foams and some co-wash/low-irritation body washes) can use it as a primary surfactant system, with active-matter equivalents commonly landing around ~5–15% and reaching about ~20% in aggressive-but-OTC rinse-off concentrates. It is rarely used meaningfully in leave-on products except at trace levels from solubilized cleansing systems, so the upper end is primarily relevant to rinse-off products and depends on whether the stated percentage refers to supplied raw material vs active matter.