Contact Allergy and Allergic Contact Dermatitis From Propylene Glycol and Related Glycols: Cosmetic Skin Sensitisers After All?
Propylene glycol contact allergy detected in 2.79% of patch-tested patients.
Contact Allergy and Allergic Contact Dermatitis From Propylene Glycol and Related Glycols: Cosmetic Skin Sensitisers After All?
Propylene glycol (propylene glycol) is widely used in cosmetic and pharmaceutical products, yet data on the prevalence of contact allergy to propylene glycol and related glycols, and their potential cross-reactivity, remain limited.
To determine the prevalence of glycol contact allergy, describe clinical characteristics and assess potential cross-reactivity.
We retrospectively analysed 1979 patients patch tested at Antwerp University Hospital between January 2021 and December 2024 who were tested with at least one glycol.
Detection rates for propylene glycol increased with concentration: 5% petrolatum (1.06%), 10% aqueous (0%), 20% aqueous (0.66%), 30% aqueous (2.19%) and 100% (7.82%, selectively tested).
Pentylene glycol allergy was found in 6.74% (6/89) and caprylyl glycol in 0.77% (5% petrolatum) and 0.12% (1% petrolatum).
Propylene glycol-allergic patients were predominantly female (63.6%), with dermatitis mainly affecting the face and hands.
Cosmetics (67.3%) were the most common exposure source, followed by topical pharmaceuticals (41.8%).
Thirty percent aqueous propylene glycol appears more suitable for screening than lower concentrations, and 100% propylene glycol may improve detection in selected cases.
Cross-reactivity seems limited and is most evident among structurally similar short-chain glycols.