Symptoms such as urticaria after the third booster dose of the new coronavirus vaccine may be an adverse reaction to the vaccine, which can be observed clinically for mild symptoms and intervened with medication for severe symptoms. Symptoms of adverse reactions such as redness and swelling, pain, hardness, itching, and rash at the site of the vaccine injection may occur after vaccination, and these manifestations usually appear between a few hours and 2 days after vaccination. Mild skin symptoms are self-limiting and usually do not require special treatment. Clinical observation is sufficient, and cold compresses can be applied for discomfort. For severe symptoms such as rash and pain, anti-allergy treatment can be provided with glucocorticosteroids such as dexamethasone and methylprednisolone, as well as oral antihistamines such as loratadine. In case of more serious adverse reactions, it is recommended to go to the hospital in time; after vaccination, it is recommended to stay in the hospital for a period of time for observation; the above medications need to be used under the guidance of a clinician.