Here are two cases of allergic contact dermatitis to a chemical found in many permanent hair dyes, in temporary henna tattoos and in some inks.
Contact allergy to permanent hair dye
A 32-year-old man presented with a marked angioedematous reaction on his face, ears, scalp and neck that had started six hours after having blonde tips applied to his dark hair by a hairdresser (Figure 1). There was no involvement of the respiratory tract. He had had no reaction three years ago when he had the same hair dye applied. There was no history to suggest prior food allergy, and he was on no medications.