A comparison of the effects of oral cetirizine and inhaled beclomethasone on early and late asthmatic responses to allergen and the associated increase in airways hyperresponsiveness.
BACKGROUND
Cetirizine is a non-sedating H1 antihistamine which is effective in the treatment of allergic rhinitis and urticaria. It inhibits eosinophil and basophil chemotaxis in late cutaneous allergic reactions in skin windows. Its effect on early (EAR) and late asthmatic reactions (LAR) is less certain.


METHODS
We examined the effect on EAR and LAR of 3 days treatment with oral cetirizine (15 mg twice daily) compared with a single dose of inhaled beclomethasone 10 min prior to allergen challenge in a placebo-controlled (oral and inhaled) double-blind cross-over design with three treatment arms separated by 14 days.


RESULTS
Cetirizine did not significantly inhibit either the EAR or LAR documented by maximum percentage fall in FEV1 (0-3 and 6-9 h) or as area under the curve (AUC between 0 and 3 and 6-9 h). Beclomethasone inhibited the LAR compared with placebo (P = 0.02) when expressed as AUC (6-9 h). This did not quite reach statistical significance (P = 0.06) when expressed as maximal percentage late fall in FEV1 between 6 and 9 h. A greater than twofold increase in airways responsiveness to methacholine was observed 3 h after challenge which was significantly reduced by beclomethasone compared with placebo (P < 0.02) and cetirizine (P < 0.05). The data suggest that oral cetirizine does not significantly inhibit either the EAR or LAR. Beclomethasone inhibited both the early increase in airways responsiveness and the subsequent LAR. Our study also confirms the view that early increases in airway responsiveness precede the late response and suggests that these associated events are not dissociable by the pharmacological treatments employed in this study.
Bentley
A M
AM
Department of Allergy & Clinical Immunology, National Heart & Lung Institute, London, UK.
Walker
S
S
Hanotte
F
F
De Vos
C
C
Durham
S R
SR
D000280:Administration, Inhalation; D000284:Administration, Oral; D000328:Adult; D000485:Allergens / Q000276:immunology*; D039741:Antigens, Dermatophagoides; D001249:Asthma / Q000188:drug therapy* / Q000276:immunology / Q000503:physiopathology; D001507:Beclomethasone / Q000008:administration & dosage* / Q000627:therapeutic use*; D016535:Bronchial Hyperreactivity / Q000139:chemically induced / Q000209:etiology*; D017332:Cetirizine / Q000008:administration & dosage* / Q000627:therapeutic use*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006023:Glycoproteins / Q000276:immunology; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000276:immunology; D008297:Male; D008875:Middle Aged; D006109:Poaceae / Q000276:immunology; D013997:Time Factors
D000485:Allergens; D039741:Antigens, Dermatophagoides; D006023:Glycoproteins; D001507:Beclomethasone; D017332:Cetirizine