The disease is a type I allergic reaction, and the allergens are mostly drugs, food, inhalants, etc. The most common allergic drugs are: sulfonamides, antibiotics, aspirin, indomethacin and other antipyretic and analgesic drugs; foods such as strawberries, fish, crabs, dairy products, pickled foods; inhalants such as animal dander, feathers, etc. In addition, environmental factors such as cold stimulation, sunlight exposure, mood swings, etc. can also trigger the disease. Suggestions: 1. Remove the cause of the disease: Please carefully recall whether there is any suspicious trigger before each attack, stop using suspicious drugs or food as soon as possible, and remember to avoid triggering factors. 2. Anti-allergy treatment 3. Please carry anti-allergy medications such as prednisone or dexamethasone type medications with you. Always keep anti-allergy medication in your room, in an obvious place within reach, where the whole family knows where to put it, in case of urgent need. Do not take it lightly! 4. If the swelling is obvious and affects pronunciation, eating and swallowing or breathing, please send to the nearest hospital as soon as possible!