1. Look at the symptoms
Nose itching, nasal congestion, sneezing, these several symptoms appear at least two, a day of up to an hour or more, accompanied by reduced sense of smell, itching eyes, etc.
2. Physical Signs
When doing nasal endoscopy, it can be found that the nasal mucosa is pale and edema, and there are watery secretions in the nasal cavity, etc.
3. Laboratory examination
Allergen skin prick test, or blood sampling for serum specific IgE, a variety of allergens, etc.