Cetirizine treatment of rhinitis in children with pollen allergy: evidence of its antiallergic activity

BACKGROUND: Cetirizine is an antihistamine, largely used in the treatment of allergic rhinoconjunctivitis, which also exerts anti-allergic activity. OBJECTIVE: To evaluate cetirizine as treatment for children with rhinitis due to pollen allergy, and to evaluate its anti-allergic activity in such a clinical condition. METHODS: The study was designed as parallel groups, double-blind, placebo-controlled, randomized. Twenty allergic children were enroled and subdivided in two groups, receiving a 4 week treatment during the pollen season. The following parameters were monitored: clinical symptoms evaluated by the allergist before and after treatment and by the patients through a daily diary card, inflammatory cells count, expression of ICAM-1 on nasal epithelial cells, inflammatory mediator levels in nasal lavage and peripheral blood before and after treatment, and pollen counts. RESULTS: This study shows that cetirizine treatment is able to reduce: clinical symptoms (P < 0.01), inflammatory cell infiltrate (P < 0.03), ICAM-1 expression on epithelial cells (P < 0.05), and soluble ICAM-1 (P < 0.05) and ECP (P < 0.05) in nasal lavage. CONCLUSION: Cetirizine is able to clinically improve nasal symptoms due to pollen allergy and to reduce allergic inflammation, which is related to allergen exposure.