ABSTRACT

Ketotifen is a cycloheptathiophene derivative that selectively blocks histamine H1 receptors and prevents the typical symptoms caused by histamine release. This agent also interferes with the release of inflammatory mediators from mast cells involved in hypersensitivity reactions, thereby decreasing chemotaxis and activation of eosinophils. This chapter provides monographs of ketotifen which have caused contact allergy/allergic contact dermatitis. The monographs present: identification section; contact allergy (general population, patients with dermatitis, case reports and case series); cross-reactions; patch test sensitization; photocontact allergy; and immediate contact reactions (contact urticaria). The identification section presents IUPAC names, synonyms, CAS and EC numbers, structural and chemical formulas, Merck Index monographs, and advises on patch testing. The chapter also covers an extensive amount of information to benefit dermatologists, allergists, and all others interested in drug allergy.