1,2-Propanediol (propylene glycol) is a small diol used in skincare as a humectant, solvent, and penetration enhancer, helping retain moisture and dissolve other ingredients. It is widely used as a formulation base across cosmetic and topical products.
| Reported effect | How often | Notes |
|---|---|---|
Skin irritation | Uncommon | Mild stinging or irritation can occur, especially at higher concentrations or on compromised skin. |
Allergic contact dermatitis | Rare | Documented sensitization in patch-test studies; relevant for individuals with propylene glycol allergy. |
Contact urticaria | Very rare | Isolated reports of immediate hive-like reactions on exposure. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
Peer-reviewed papers on this ingredient, via PubMed.