Nasal allergen challenge - an important tool in diagnosis of rhinologic disease

The nasal allergen challenge (NAC) is used in the diagnosis of rhinitis. The primary use of NAC is to confirm allergy to a specific inhaled allergen. NAC reproduces the allergic reaction of the nasal mucosa under standardized and controlled conditions that occurs after direct intranasal administration of allergens. As the only used method for assessing the degree of allergy, it mimics the body’s natural response to the sensitizing factor in the early and late stages of an allergic reaction. NAC is used in the diagnosis of chronic, occupational and local rhinitis, as well as in the differential diagnosis of rhinitis and ophthalmic symptoms. Under conditions similar to natural exposure, it determines the relationship between the allergen and symptoms of allergic rhinitis, especially in the case of difficulties in interpreting the results of skin tests and the serum concentration of specific IgE. It is a truly valuable tool in determining the indications for immunotherapy and the selection of allergens for desensitization therapy. It also serves as a method of monitoring the effectiveness of immunotherapy and pharmacotherapy. For scientific purposes, NAC is used to study the mechanisms of an allergic reaction and the influence of various factors on its course. It is considered safe, but requires appropriate instruments and qualified personnel.