100166 - Contact urticaria with phenoxyethanol

Background

Contact urticaria (CU) is a skin response with the formation of hives within 30-60 minutes after the application of a product, which can remain for up to 24 hours without leaving persistent signs.

Phenoxyethanol is an aromatic alcohol with antimicrobial properties, commonly used as a preservative in cosmetics, vaccines, and wound care medications. Its maximum permitted concentration is 1% (also the concentration for the epicutaneous patch test). It is a rare allergen with a patch positivity frequency of 0.2-0.24%, and acts with an immunological mechanism.

CASE REPORT AND RESULTS

A 45-year-old woman had been reporting outbreaks of hives after contact with various topical products for a year and was diagnosed with contact urticaria.

Since the main suspicion was benzyl alcohol, an open test was performed and another with a 20-minute patch occlusion with 10% benzyl alcohol (Chemotechnique). Both were negative after 60 minutes.

She was told to bring the products she normally used, including those that had caused the symptoms. After a thorough inspection of the ingredients of these products, it was verified that phenoxyethanol was present in the products that had caused the symptoms and absent in those she normally used.

An open test was performed with 1% phenoxyethanol in petrolatum, which was positive 10 minutes after applying it.

She was diagnosed with contact urticaria due to phenoxyethanol, so she was told to avoid products containing it.

CONCLUSIONS

1. We report a case of contact urticaria due to phenoxyethanol present in different cosmetic products.

2. There are only 12 reported cases of CU with phenoxyethanol so is a very rare and infrequent allergen but it important to keep in mind since it is frequently used in cosmetics.

3. The patient should avoid cosmetics containing phenoyethanol.