Sodium pyrrolidone carboxylate (Sodium PCA) (Sodium PCA)

Sodium PCA, the sodium salt of pyrrolidone carboxylic acid (also known as pyroglutamic acid), is a naturally occurring component of human skin and a key constituent of the Natural Moisturizing Factor (NMF) [PubChem CID 23662322]. It is highly hygroscopic, allowing it to attract and retain moisture from the surrounding environment, which is essential for maintaining skin hydration and elasticity [Cosmetic Ingredient Review, 2019]. Sodium PCA is not a conventional therapeutic target, such as a receptor or enzyme; rather, it is used as an active ingredient in topical dermatological and cosmetic products to treat dry skin conditions like xerosis and atopic dermatitis [NIH/PubMed]. Its biological role is primarily homeostatic within the stratum corneum, where it supports the skin's barrier function and maintains moisture balance. While it is generally recognized as safe, non-toxic, and non-sensitizing, careful formulation is required to prevent the formation of carcinogenic nitrosamines when used in combination with nitrogen-containing preservatives [CIR Expert Panel].

Other names

Sodium pyroglutamateSodium L-pyroglutamateSodium 5-oxo-L-prolinatePCA-NaL-Proline, 5-oxo-, monosodium saltMonosodium L-pyroglutamate

Sodium PCA functions as a powerful humectant by attracting and binding water molecules to the stratum corneum through hydrogen bonding, thereby increasing skin hydration and improving barrier function.