Approach to allergic contact dermatitis caused by topical medicaments

Area of Science:

• Dermatology
• Allergology
• Pharmacology

Background:

• Allergic contact dermatitis (ACD) from topical medications is often overlooked.
• It can present similarly to other eczematous eruptions, complicating diagnosis.
• Identifying specific allergens is key for effective patient management.

Purpose of the Study:

• To develop an approach for identifying topical medicament ingredients that cause ACD.
• To recognize common clinical scenarios associated with these allergens.
• To improve diagnostic accuracy and patient outcomes in ACD cases.

Main Methods:

• Retrospective chart review of patients undergoing patch testing.
• Inclusion of data from the North American Contact Dermatitis Group and Ottawa Hospital patch test clinic.
• Analysis of patient data to identify common allergens and clinical presentations.

Main Results:

• Topical antibiotics are the most frequent cause of medicament-induced ACD, often leading to co-sensitization.
• Corticosteroid allergy can be subtle, presenting as worsening dermatoses despite treatment.
• Topical anesthetics and propylene glycol are also significant contributors to ACD.

Conclusions:

• ACD should be considered in all eczematous eruptions.
• A comprehensive drug history, including all topical products, is essential.
• Patch testing is a valuable tool for identifying specific allergens and guiding avoidance strategies.