Temporary henna tattoos are a popular fashion accessory in recent years. The tattoo dye consists of henna extract from the plant Lawsonia, and p-phenylenediamine to create a darker shade to the tattoo. Increasingly, emergency departments are seeing children with atopic reactions to these tattoos. The p-phenylenediamine component can cause a spongiotic dermatitis with lympho-histiocytic infiltrates. I present two cases of reactions to temporary tattoos in children attending the emergency department. The acute management of these cases and the possible future consequences of sensitization to p-phenylenediamine are discussed.