EFFECTS OF TOPICAL BUDESONIDE AND LEVOCABASTINE ON NASAL SYMPTOMS ANDPLASMA EXUDATION RESPONSES IN SEASONAL ALLERGIC RHINITIS

This study compares the effects of two topical nasal treatments for al lergic rhinitis, budesonide and levocabastine, on symptom development during seasonal pollen exposure. Additionally, the protective effects of drug treatments on allergen-challenge-induced responses (symptoms a nd microvascular exudation of plasma) are examined late into the polle n season. Forty-four patients with seasonal allergic rhinitis to birch pollen participated in this single-blind, randomized, and placebo-con trolled study. Topical nasal treatment with either levocabastine (200 mu g b.i.d,; n=16), budesonide (200 mu g b.i.d.; n=16), or placebo (n= 12) was instituted before the start of the pollen season and continued for 5 weeks until the end of the birch pollen season. The participant s kept diaries for scores of nasal and ocular symptoms. Nasal allergen challenges with increasing doses of a birch pollen extract (10(2), 10 (3), and 10(4) SQ-U) were carried out both before, when patients were asymptomatic and without treatment, and late into the pollen season. A nasal lavage followed each challenge, and the lavage fluid levels of albumin were measured as an index of the acute inflammatory response o f the allergic mucosa. The birch pollen season was rather mild, produc ing only small increases in nasal symptoms. Budesonide treatment reduc ed the total nasal symptoms compared to placebo (P<0.01) and to levoca bastine (P<0.05), while levocabastine treatment did not differ signifi cantly from placebo. Ocular symptoms and use of rescue medication did not differ between placebo and the active treatments. At the end of th e pollen season, both treatments reduced allergen-challenge-induced na sal symptoms compared to placebo (P<0.01). Only budesonide reduced all ergen-challenge-induced increments of albumin levels in postchallenge nasal lavage fluids (P<0.05, in comparison with placebo). The results suggest that budesonide reduces both seasonal and allergen-challenge-i nduced nasal symptoms, while levocabastine is effective against allerg en-challenge-induced symptoms also during the season. In addition, the topical steroid treatment, but not the antihistamine, inhibits the in flammatory exudation evoked by allergen challenge in patients with act ive seasonal disease.