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Sodium PCA
Sodium PCAHydrator
One of skin’s own moisture-holding molecules, bottled. It hydrates about as well as glycerin.
What it does
It’s part of skin’s natural moisturizing factor, the mix of small molecules in the top layer that holds water and keeps the surface flexible. On skin it pulls in water about as well as glycerin.
The EU’s ingredient database lists it as a humectant (helps hold in moisture).European Commission, CosIng (© European Union, CC BY 4.0) · uses put in plain words by Drop ↗
The evidence, graded
strongOne application of a ceramide cream lowered water loss through the skin, measured from two hours and held to 24 hours, and raised skin hydration over the same day. Hyaluronic acid creams improved skin hydration and elasticity when measured at 30 and 60 days. Neither source Drop has read measured how long barrier repair takes, so Drop sets no barrier-repair window.Pavicic 2011 · Journal of Drugs in Dermatology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
sodium pyrrolidone carboxylate
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