The side effects of magnetic resonance contrast agent mainly include gadolinium ions inside the magnetic resonance contrast agent, which are free in the body and produce toxic side effects on the human body; high permeability, which causes blood volume expansion; the contrast agent may produce specific toxic effects on some organs of some patients. In general, the side effects caused by MRI contrast agents can be classified as mild, moderate or severe, as follows: 1. Mild: nausea and vomiting can occur, and patients’ vital signs need to be closely monitored; 2. Moderate: peripheral nerve symptoms, such as itching and abnormal sensation, can occur, and treatment with anti-allergy drugs can provide appropriate relief; 3. Severe: patients will have laryngeal edema, anaphylaxis, syncope, etc., and need to be treated with epinephrine or for volume expansion, or even for cardiopulmonary resuscitation treatment.