Hydroxyectoin

HYD

8/10

Concern level

High concern

Hydroxyectoin is a small, water-soluble ectoine derivative used in cosmetics as a skin-conditioning, buffering, and emollient ingredient. It functions as an osmolyte-compatible solute, helping formulas support hydration and stress protection while remaining generally well tolerated. PubChem lists Hydroxyectoin as 5-hydroxyectoine with a molecular weight of 158.16 g/mol, and CosIng/COSMILE identify it as a permitted cosmetic ingredient with skin-conditioning and buffering functions. ([pubchem.ncbi.nlm.nih.gov](https://pubchem.ncbi.nlm.nih.gov/compound/5-Hydroxyectoine?utm_source=openai))

Pore-clogging

Non-comedogenic

Pregnancy

Safe

Regulatory

No data

Benefits

MoisturizingSoothingSupports Barrier Function

Chemical Properties

Molecular Weight

158.16 g/mol

pH Range

1.00 - 9.00

Typical Concentration

0.50% - 2.00%

CAS Number: 165542-15-4

Skin Type Compatibility

dry skin9/10

oily skin7/10

sensitive skin9/10

acne prone8/10

mature skin8/10

normal skin9/10

Interactions

incompatible with: No well-established problematic ingredient interactions are documented in the sources reviewed., Because it is a water-soluble conditioning active, it is generally used alongside humectants, barrier lipids, and soothing agents rather than as a high-pH exfoliating active.

Risks & Warnings

Low overall risk profile in topical cosmetic use, with the main practical concern being the usual possibility of mild individual sensitivity or formula-dependent irritation. It is not known as a strong sensitizer or comedogenic ingredient. Available cosmetic database listings do not show a specific EU restriction record, but that does not replace full formula safety assessment. ([cosingchecker.com](https://cosingchecker.com/ingredients/85541-hydroxyectoin/?utm_source=openai))

Vegan Cruelty-Free

Found In Products

Skinfix