OBJECTIVES Regulated on activation normal T cell expressed and secreted (RANTES) and eotaxin-2 have been postulated to be responsible for eosinophilia in chronically inflamed nasal mucosa. This study evaluated mucosal production of RANTES and eotaxin-2 in patients with perennial allergic rhinitis (PAR) and nonallergic and allergic form of chronic rhinosinusitis with nasal polyps (CRSwNP) before and after nasal corticosteroid treatment. METHODS Twenty patients with PAR, 20 nonallergic and 20 allergic CRSwNP patients, and 20 healthy controls were included. The RANTES and eotaxin-2 levels were measured in nasal secretion samples. The patients with chronic inflammation were treated with fluticasone furoate nasal spray for 2 weeks. Cytological examination and measurement of RANTES and eotaxin-2 in nasal fluid were performed before and after the treatment. RESULTS The levels of RANTES were higher in patients with PAR ( P < .05) and nonallergic ( P < .01) and allergic CRSwNP patients ( P < .001) compared to controls. Eotaxin-2 levels were higher in all 3 inflammation groups compared to healthy subjects ( P < .001). After the treatment, we found a significant decrease of RANTES and eotaxin-2 concentrations ( P < .001) in all 3 groups of patients. CONCLUSION The levels of RANTES and eotaxin-2 in nasal fluid could be reliable markers for assessing corticosteroid administration outcomes.