Temporary tattooing using henna dye, a dark green power made from the leaves of the henna (Lawsonia inermis) plant has become very popular in recent years, both among adults and children. A recent article in the Journal of Dermatology details the case of a 9-year-old boy who developed allergic contact dermatitis after receiving a henna tattoo. Testing showed the boy had an allergy to para-phenylenediamine (PPD), the chemical often added to henna dye to make the color blacker and to speed up the dyeing process. After treatment with a cortocosteroid cream and oral antihistamines, the lesion went away, although some residual hypopigmentation remained.
Henna tattooing is not as risk-free as it seems. “The active substance from henna leaves is naphthoquinone,” the article’s authors note. “But for dying and tattooing, henna dye is usually mixed with other darkness-enhancing substances, such as PPD or para-toluenediamine, both very potent contact allergens. Heavy metals, such as nickel, cobalt, chromium, lead and mercury, also potentially strong contact allergens, can be found in henna tattoo mixtures.”
Topical corticosteroids and oral antihistamines are usually all that’s needed to treat these allergic reactions, the authors added, although in some cases a short-term systemic corticosteroid may also be needed.
Source: Jovanovic DL, Slavkovic-Jovanovic MR. Allergic contact dermatitis from temporary henna tattooing. J Dermatol. 2009:36:63-65.