Contact dermatitis to temporary tattoo.

The development of contact hypersensitivity to temporary tattoos has been on an increase all over the world. Skin painting with henna is a traditional practice in the Moslems and Hindu, and has recently been increasingly used in western countries. Black henna is obtained by adding paraphenylenediamine to the natural occurring henna. The risk of sensitization increases with the length of contact and increase of the concentration. A case is presented of an 11-year-old boy who developed a severe reaction in the form of redness and edema accompanied by pruritus on the day following the application of a temporary tattoo. A year before, the patient had also developed a skin reaction following temporary tattooing, which had not been recognized as a contact dermatitis. Patch testing was positive for paraphenylenediamine and thiuram compounds. The patient was treated with medium-strength corticosteroids.