Skin Conditioning

Allantoin Acetyl Methionine

INCI: ALLANTOIN ACETYL METHIONINE
CAS 4207-40-3 EC 224-126-2
N-acetyl-DL-methionine, compound with (2,5-dioxo-4-imidazolidine)urea (1:1)
Limited Data
Insufficient safety data available. Consider enriching this ingredient.
Details

Description

N-acetyl-DL-methionine, compound with (2,5-dioxo-4-imidazolidine)urea (1:1)

Purpose

Function

Antistatic, Skin Conditioning, Skin Protecting, Soothing
Profile

Properties

Silicone
Silicone free
Compliance

Regulatory Status

EU
Permitted
Safety
GOOD
US
Permitted
Absorptionlow
Sensitizationnone
MoSnot established
ConcernModerate
Verdict

Data gap: not included in CIR final report. Safety is inferred from parent compounds (allantoin + N-acetyl-DL-methionine). Both parent compounds have strong safety profiles, but the complex itself lacks independent toxicological data.

US Note

Not restricted; not specifically covered by the CIR allantoin complex review (that review covered ascorbate, biotin, galacturonic acid, glycyrrhetinic acid, panthenol, polygalacturonic acid — not acetyl methionine)

Assessment

Ratings

Comedogenic0/5
LowHigh
Irritancy0/5
LowHigh
Reference

Identifiers

CAS Number
4207-40-3
EC Number
224-126-2
INCI
ALLANTOIN ACETYL METHIONINE
Category
Skin Conditioning
Updated
Apr 2, 2026