The time for hives to disappear cannot be generalized, and is related to the patient’s physical condition, the severity of the condition, and whether or not anti-allergy treatment has been administered, so the exact time varies from person to person. If the patient’s condition is mild, only localized urticaria, detached from the allergen and anti-allergy treatment can subside in a few hours, do not worry too much. If the patient’s condition is more severe, with hives all over the body, and the allergen is not known, the hives will last longer, and anti-allergy drugs, such as loratadine, cetirizine, or ibastine, should be taken promptly, and the duration may be several days or weeks. When urticaria occurs, you should actively search for allergens and avoid contact with such substances to avoid recurrent episodes of the disease, and the above medications should be used under the guidance of a doctor.