ABSTRACT
Contact urticaria is a wheal and fl are reaction of the skin following external contact to an ever-expanding list of simple chemicals or macromolecules [1], which are usually substances encountered frequently in our environment as preservatives or fragrances and fl avorings in cosmetics, toiletries, topical medicaments, and foodstuffs [2,3]. Nonimmunological contact urticaria means a reaction without any previous sensitization and is supposed to be the commonest form. Immunological contact urticaria (ICD) is a Type I hypersensitivity reaction in previously sensitized individuals and is mediated by allergen-specifi c IgE. Symptoms of ICD span from simple localized wheal and fl are to generalized urticaria with involvement of internal organs such as the respiratory or gastrointestinal tract and may culminate in a life-threatening anaphylactic shock [1].
