Abstract
The effects of the β-adrenoceptor stimulating drugs, terbutaline (Bricanyl®) and KWD 2131, on the increase in nasal airway resistance induced by pollen extracts, have been studied in a placebo-controlled double-blind crossover trial of 13 asymptomatic (out of season) patients with hay fever. For objective evaluation of the nasal airway resistance posterior rhinomanometry has been used. The rhinomanometric measurements indicated an antianaphylactic effect of terbutaline and KWD 2131, but rhinoscopy and the patients' own opinion could not establish such an effect. The design of the trial made it possible to establish whether or not an increased or a decreased nasal obstruction due to repeated challenges occurred. Despite 6 preceding nasal provocations in each participant, neither increased (‘priming effect’) nor decreased (hyposensibilization) reaction was detected in the following challenge.