URTICARIAL REACTION FOLLOWING THE INHALATION OF NICOTINE IN TOBACCO-SMOKE

We report a patient with recurrent generalized itching and urticaria d ue to inhalation of nicotine in tobacco smoke. A skin prick test with nicotine base (1:10 w/v) was negative but an intradermal test with nic otine base (1:100 w/v) was strongly positive. Intradermal tests with n icotine base (1:100 w/v) performed on 10 healthy controls were negativ e. A provocation test, with a nicotine patch showed the same symptoms and signs including generalized itching, weals and flares, and mild dy spnoea, which occurred when he was exposed to tobacco smoke. Nicotine in tobacco smoke can act as an inhalant allergen and induce urticaria in hypersensitive persons.