Acetyl Arginine

Acetyl Arginine 1
molecular structure · PubChem CID 16218842
AKA: 210545-23-6, Ac-Arg-OH dihydrate, (S)-2-Acetamido-5-guanidinopentanoic acid dihydrate, AC-ARG-OH 2H2O, L-Arginine, Hydrate (1:2), N-ACETYL-L-ARGININE DIHYDRATE, N-Acetyl-L-arginine (dihydrate), Ac-Arg-OH.2H2O, (2S)-2-acetamido-5-(diaminomethylideneamino)pentanoic acid;dihydrate
Synthetic
Humectant
Emollient
Skin Conditioner
Amino Acid
Not Clean
OriginAcetyl arginine is synthesized from L-arginine, a naturally occurring amino acid, combined with acetic acid or acetyl compounds. It is produced through acetylation, a chemical process that attaches an acetyl group to the arginine molecule.
L- Arginine, N(2)-acetyl-
Formula
C8H20N4O5
Mol. Weight
252.27
CAS #
210545-23-6
Form
Liquid
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
Functions
Humectant
A moisture magnet. Pulls water from the air and deeper skin layers up to the surface to keep skin plump and hydrated.
Skin Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Emollient
Fills in the tiny cracks between skin cells to make everything feel smooth and soft. The "silky finish" ingredient.
Locks In Moisture
The paper trail
🔬Peer-reviewed1 paper →
⚖️Regulatory1 listing →
🛡️Safety-assessed1 review →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
EWG
4
CIR
Safe as used
Pregnancy
Yes
Concentration Guide
CIR lists it as not reported to be in use.
CIR · report published 2017
Regulatory Status
USA✔ permitted
EU⚠ restricted
JAPAN⚠ restricted
CANADA⚠ restricted
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR