Allergic contact dermatitis to an expired moisturiser

Area of Science:

• Dermatology
• Allergology
• Cosmetic Science

Background:

• Allergic contact dermatitis (ACD) is an immune response to topical agents.
• Sorbolene cream is a common, widely used over-the-counter moisturizer.
• Expired topical products are generally considered safe if stored properly.

Observation:

• A 64-year-old male presented with ACD after using expired sorbolene cream.
• Standard patch testing to individual ingredients of the sorbolene cream was negative.
• Open application testing showed a reaction to the expired cream but not to a non-expired identical product.

Findings:

• The expired sorbolene cream contained an unidentified allergen, likely a degradation product.
• The allergen was not present in the original formulation of the cream.
• This case highlights a rare instance of ACD caused by an expired topical product.

Implications:

• Expired topical products may harbor novel allergens due to degradation.
• Clinicians should consider expired product use in cases of unexplained ACD.
• Further research is needed to identify common degradation allergens in expired cosmetics.