Body & Beauty / Compounds / Allantoin

Allantoin on your skin: a safety profile

Low risk

(People-specific data is limited; this page draws from human adult context.) Safety profile for Allantoin relevant to people.

What is allantoin?

The IUPAC name is (2,5-dioxoimidazolidin-4-yl)urea.

Also known as: (2,5-dioxoimidazolidin-4-yl)urea, 1-(2,5-dioxo-4-imidazolidinyl)urea, 5-ureidohydantoin, glyoxyldiureide.

IUPAC name
(2,5-dioxoimidazolidin-4-yl)urea
CAS number
97-59-6
Molecular formula
C4H6N4O3
Molecular weight
158.12 g/mol
SMILES
C1=CN=CC=C1C2=CC(=C(N=C2)O)N
PubChem CID
5281003

Risk for people

Low risk

Regulatory consensus

3 regulatory and scientific bodies have classified Allantoin. The classifications differ — that's the data.

AgencyYearClassificationNotes
EU_CLP—Acute Tox. 4 (Oral)H302: Harmful if swallowed
INCI——Approved cosmetic ingredient; INCI Name: ALLANTOIN
FDA——OTC monograph ingredient; skin protectant (21 CFR 347.10)

Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.

Where you encounter allantoin

  • skincare creams
  • wound care products
  • protective formulations
  • pharmaceutical preparations

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Allantoin:

  • Glycerin (plant-derived) — gold standard humectant, excellent safety profile
    Trade-offs: Consumer preference for 'natural' label; many natural fragrance compounds are potent allergens (limonene, linalool, eugenol); 'natural' ≠ 'safe'; often more expensive than synthetic equivalents.
    Relative cost: 2-5× conventional
  • Hyaluronic acid — naturally occurring, very low sensitization potential
    Trade-offs: Removes 95-99% of dissolved contaminants including metals, PFAS, nitrates; wastes 2-4 gallons per gallon produced (improving with newer systems); removes beneficial minerals; $0.05-0.25/gallon; requires pre-treatment for longevity.
    Relative cost: 2-5× conventional
  • Panthenol (provitamin B5) — well-tolerated, additional skin-soothing properties
    Trade-offs: Removes 95-99% of dissolved contaminants including metals, PFAS, nitrates; wastes 2-4 gallons per gallon produced (improving with newer systems); removes beneficial minerals; $0.05-0.25/gallon; requires pre-treatment for longevity.
    Relative cost: 1.2-2×

Frequently asked questions

What products contain allantoin?

Allantoin appears in: skincare creams; wound care products; protective formulations.

Why do regulators disagree about allantoin?

Allantoin has been classified by 3 agencies including EU_CLP, INCI, FDA, with differing conclusions. Regulators apply different standards of evidence (animal data weighting, exposure-pattern assumptions, epidemiological power thresholds), which is why two scientific bodies can review the same data and reach different conclusions. See the regulatory consensus table on this page for the full picture.

See Allantoin in the body app

Look up products containing allantoin, compare to alternatives, and explore the full data record.

Open in body View raw API data

Sources (2)
  1. PubChem Compound CID 5281003 — database
  2. ATSDR Toxicological Profile — CAS 97-59-6 — reference

Reference data, not professional advice. Aggregates publicly available regulatory and scientific data; not a substitute for veterinary, medical, legal, or regulatory advice. Why we built ALETHEIA →