Contact dermatitis of the ear due to a rubber earplug.

We report a case of contact dermatitis of the ear canal due to rubber earplugs. A 31-year-old Japanese woman had a 2-year history of eczema confined to her ears. Applications of various topical steroids had shown no beneficial effect upon her lesions. Considering contact dermatitis as a possible diagnosis we performed patch tests. Positive eczematous patch test results were obtained with mercaptobenzothiazole, tetramethylthiuram disulfide and her rubber earplugs, which she had used whenever she took a bath. The eruption cleared after the patient stopped using the rubber earplugs.