PLACEBO-CONTROLLED CHALLENGES WITH PERFUME IN PATIENTS WITH ASTHMA-LIKE SYMPTOMS

A group of nine patients with respiratory symptoms after nonspecific i rritating stimuli, but without any IgE-mediated allergy or demonstrabl e bronchial obstruction, were referred to the asthma/allergy outpatien t department for evaluation of suspected asthma. In order to find a pr ovocation model and objectively assess these patients' symptoms in con trolled studies, provocation with perfume or placebo was performed. Th e same patients were also subjected to perfume provocation with or wit hout a carbon filter mask to ascertain whether breathing through a fil ter with active carbon could prevent the symptoms. The patients breath ed through the mouth during the provocations, as they used a nasal cla mp to prevent any smell of perfume. We found that the patients' earlie r symptoms could be verified by perfume provocation. Breathing through the carbon filter had no protective effect. The conclusion is that sy mptoms suggesting hyperreactivity of the respiratory tract and asthma can be provoked by perfume without the presence of bronchial obstructi on, and that using a carbon filter mask has no preventive effect. The symptoms are not transmitted via the olfactory nerve, since the patien ts could not smell the perfume, but they may have been induced by a tr igeminal reflex via the respiratory tract or by the eyes.