Contact dermatitis from a presumed allergy to paraphenylenediamine.

Paraphenylenediamine (PPD) is a potent skin allergen found in permanent hair dye and temporary henna tattoo ink. Several cases of adverse skin reactions to PPD have been reported in the literature. Here we present a case involving a patient who acquired a temporary tattoo while vacationing in Mexico and subsequently developed contact dermatitis at the tattoo site. He provided a history of permanent hair dye use in the past with associated cutaneous reaction. Temporary tattoos have become increasingly popular with travelers and as a result so have reports of associated allergic contact dermatitis. Of concern is cross-reaction of PPD to related compounds, severe reactions in younger populations and sequelae including increased sensitization, permanent scarring, and persistent postinflammatory hyperpigmentation.