Iodine allergic reactions can occur immediately after administration or after a few hours. The main reactions include the following: i. Mild reactions: hives, facial flushing, salivation, sneezing, lacrimation, chest tightness, shortness of breath, nausea and vomiting. Mild allergic reactions can be relieved by themselves within a short period of time without special treatment; ii. Severe reactions: 1. For neurovascular edema, 25-50mg of isoproterenol can be injected intramuscularly. For laryngeal or bronchospasm, 0.1% epinephrine, 0.5-1ml, or 0.5-1.5g of aminophylline can be injected subcutaneously or intramuscularly, and 100-400mg of hydrocortisone can be injected intravenously, or 5-10mg of dexamethasone can be injected intramuscularly to suppress the allergic reaction in the organism. In addition, oxygen, tracheal intubation, artificial respiration, cardiac compressions, antiepileptic and anti-shock treatment are given according to the situation.