For more severe cases of urticaria, intravenous infusion is recommended. For example, if the rash is widespread, if there is abdominal discomfort, if there is anaphylaxis, or if there is laryngeal edema, it is recommended that intravenous access be established and intravenous fluids be given. In cases of widespread urticaria, shock, anaphylaxis and laryngeal edema may occur due to severe itching or extravasation of body fluids, and intravenous access should be established promptly. Some patients with urticaria may also experience gastrointestinal discomfort, such as nausea, vomiting, abdominal pain and other conditions, which also require the establishment of intravenous access, active rehydration, for recurrent episodes of oral medication can not control the urticaria, can also be given intravenous infusion treatment.