The Spectrum of Antihistamines Adversely Affecting Pulmonary Function in a Subset of Asthmatic Children*

The safety of using conventional antihistamines in bronchial asthma remains controversial. In this study, 5 asthmatic children who reported increased asthma symptoms with antihistamine use were orally challenged with a spectrum of antihistamines (brompheniramine maleate, chlorpheniramine maleate, diphenhydramine HCl, hydroxyzine HCl, and pyribenzamine HCl) while off bronchodilators. Results indicated a statistically significant fall in pulmonary function values from baseline, maximal at 60 min post-challenge, for all drugs tested. Therefore, a subset of asthmatic children does appear to exist in whom the use of conventional antihistamines may be harmful unless accompanied by the concomitant use of a bronchodilator.