A nasal smear can sometimes be helpful for establishing the diagnosis of allergic rhinitis. A sample of secretions and cells is scraped from the surface of the nasal mucosa using a special sampling probe. Secretions that are blown from the nose are not adequate. The presence of eosinophils is consistent with allergic rhinitis but also can be observed with NARES. Results are neither sensitive nor specific for allergic rhinitis and should not be used exclusively for establishing the diagnosis.