Urticaria is commonly known as rubella. It is a limited edematous reaction due to dilatation of small blood vessels in the skin and mucous membranes and increased permeability, which usually subsides within 2 to 24 hours, but new rashes occur repeatedly. The course of the disease is prolonged for several days to several months. It even becomes chronic and is more common in clinical practice. The cause of urticaria is very complex, and about 3/4 of patients cannot find the cause, especially chronic urticaria. The common causes are: food and food additives; inhalants; infections; drugs; physical factors such as mechanical stimulation, heat and cold, sunlight, etc.; insect bites; mental factors and endocrine changes; genetic factors, etc. Then suffering from hives, what are the precautions? 1, from the patient’s own diet and living environment and other specific circumstances, and actively seek the cause of the disease, and keep a daily record. Such as eating sea fish, shrimp and crab, longer storage of meat products, the recent history of medication, bacteria, viruses, parasitic infections, seasonal changes, mental stress, mosquito bites, etc., through the diary method of life to self-adjustment. 2, during the onset of the appropriate “taboo”. Daily diet should be light and easy to digest. Avoid tobacco, alcohol, seafood, spicy and sour food, cold, hard oil, and spoiled food, and pay attention to whether there are any abnormal symptoms in the body; wait for the condition to gradually stabilize before resuming the previous diet. Once a food is considered to cause hives, it should be put on the “black list” and should not be consumed next time. 3, common foods that can cause hives are: seafood such as sea fish, shrimp, crab, shellfish, oysters, eggs, milk, cheese, chocolate, mangoes, pineapples, strawberries, tomatoes, lychees, peaches and dried fruits such as walnuts, almonds, hazelnuts, etc. 4.When you have a history of penicillin allergy or hives due to penicillin injection, you should avoid using dairy products because some of them may be contaminated by penicillin. 5, some patients with urticaria have allergic reactions to aspirin, non-steroidal anti-inflammatory drugs, azo dyes and preservatives, food additives, etc., which may be arachidonic acid-mediated urticaria. 6, some other contacts such as topical drugs, animals, plants, paints, industrial compounds, etc. can also cause or aggravate urticaria. 7, some patients may be allergic to fungi and their spores, should avoid eating fungal fermented foods, such as mushrooms, cheese, cream, vinegar, beer, mayonnaise, etc., while taking oral mycoplasma to kill the gastrointestinal tract of Candida albicans, to remove possible fungal allergens. 8, pay attention to hygiene. It is important to prevent mites and dust at home, and avoid contact with pollen-like substances. 9.If a female patient has severe persistent chronic urticaria, attention should be paid to laboratory tests for blood sedimentation, thyroid function, autoantibodies, etc. to exclude concomitant related autoimmune diseases. 10.If the rash lasts for 24 to 72 hours, accompanied by obvious burning and pain while itching is mild; or if the rash appears purpuric, scaly and pigmented, consider whether it is urticarial vasculitis, and pay attention to the blood sedimentation and complement tests to see if there is fever and arthralgia. 11, when taking anti-allergy drugs to follow the doctor’s instructions, encounter a cold fever abdominal pain and other symptoms, more consultation with doctors, medication especially careful, careful use of antibiotics. At the same time, you should not stop the medication on your own, otherwise it is very easy to relapse, but should be gradually discontinued under the guidance of a specialist. 12, at the same time, solemnly reminded that the symptoms of urticaria are complex and changeable, there is a sudden exacerbation of the symptoms in the process of getting better, and there may be the possibility of re-emergence after healing; there are also skin erythema, in addition to facial redness, nausea and vomiting, abdominal pain and diarrhea, chest tightness and shortness of breath, and even respiratory distress or suffocation, once it happens, we must fight every second to seek immediate medical attention. One thing to emphasize is that for the treatment of chronic urticaria, do not believe in prescriptions or rush to the doctor, must be under the guidance of a specialist to take medication, sometimes need to maintain the medication for 3 months or more, gradually control slowly will be cured.