Nasal cytological changes following pharmacological intervention.

Symptoms of allergic rhinitis are associated with increased numbers of inflammatory cells in the nasal mucosa. The effects of fluticasone propionate on the nasal mucosal cells of patients with symptomatic allergic rhinitis were evaluated in seven multicentre, double-blind, parallel-group, placebo-controlled, randomised studies. In three seasonal allergic rhinitis studies, significantly more patients receiving fluticasone propionate had a decrease in nasal eosinophils following treatment compared with patients receiving placebo. Similarly, more patients receiving fluticasone propionate had a decrease in nasal basophilic cells, but differences from placebo were not significant in all studies. Nearly identical results were observed in two 24-week perennial allergic rhinitis studies: significantly more patients receiving fluticasone propionate or beclomethasone dipropionate had a decrease in nasal eosinophils compared with patients receiving placebo. Furthermore, a higher percentage of patients receiving corticosteroids also had a decrease in the number of basophilic cells. In two separate seasonal allergic rhinitis studies, significantly more patients receiving fluticasone propionate had a decrease in nasal eosinophils compared with patients receiving terfenadine or astemizole, respectively. The decrease in nasal basophilic cells was also significantly greater with fluticasone propionate compared with astemizole. Inhibition of mediator release from eosinophilic and basophilic cells has also been demonstrated in patients receiving fluticasone propionate compared with patients receiving antihistamines. The results of these studies suggest that the therapeutic benefits of fluticasone propionate aqueous nasal spray in the treatment of seasonal and perennial allergic rhinitis may be related to its ability to reduce nasal mucosal inflammatory cells and to inhibit local mediator activity.