Background: In recent years, temporary tattoos instead of permanent tattoos have become popular worldwide. Although contact allergy to temporary henna tattoos appears to be rare in the past, it is progressively more commonly reported.
Patients: Four Taiwanese patients of allergic contact dermatitis following application of temporary tattoos were patch tested and they were followed up for 1 year after treatment.
Results: All four of the tested patients were positive to paraphenylenediamine. At 1-year follow-up, all four patients still showed various degrees of remnant hyperpigmentation on their previous tattooed areas.
Conclusion: Temporary tattoos may pose similar risks of allergic reactions associated with permanent tattoos. A high risk of prolonged post-inflammatory hyperpigmentation after allergic contact dermatitis from temporary tattoos should also be alerted, especially in Asian skin type.