MODE OF ACTION OF A TOPICAL STEROID ON IMMEDIATE PHASE REACTION AFTERANTIGEN CHALLENGE AND NONSPECIFIC NASAL HYPERREACTIVITY IN NASAL ALLERGY

This study compared the effects of 2-week administration of a topical steroid (fluticasone propionate [FP] 100 mu g twice daily) with placeb o in 28 patients with perennial nasal allergy who were allergic to hou se dust and mites in a double-blind randomized study. The number of in flammatory cells and decidual epithelial cells and concentrations of t ryptase and eosinophil cationic protein in nasal lavages, and reactivi ty of the nasal mucose to histamine and to antigen were investigated. The topical steroid, FP, significantly inhibited all of these assessme nts. The degree of improvement of nasal reactivity to histamine signif icantly correlated with the degree of decrease in eosinophil cationic protein levels.