1.Symptoms: wheezing, coughing, dyspnea, chest tightness; characteristics: especially at night; can be relieved by themselves or with medication; some patients have obvious seasonality; exposure to certain substances such as: animals with fur, inhalation of chemicals, climate change, dust mites, drugs, exercise, pollen, smoking, violent mood swings. 2, signs: doctors can hear croup in the patient’s chest, predominantly during exhalation, with prolonged expiratory limit. 3.Blood routine: there can be an increase of eosinophils. 4.X-ray: There can be no special changes, sometimes co-infection will have lung texture enhancement and inflammatory infiltration. 5.Pulmonary function test: This needs to be judged by a professional doctor, but it should be noted that it should be checked at the time of attack. Bronchial excitation and diastolic tests can be done 6. Specific allergen testing: IgE can be higher than normal.