A nasal challenge test with an allergen plays an important role in the differential diagnosis of rhinitis. As the only one in the group of available methods of rhinological and allergy diagnostics, it is helpful in diagnosing a local allergic reaction, whose incidence rate is up to 20% of all rhinitis cases. A nasal challenge test with an allergen frequently decides about further eligibility for treatment, including eligibility for allergen immunotherapy. A prerequisite for obtaining a reliable result and the safety of the provocation is strict adherence to the test procedure.