Although the amount of radiation from enhanced CT is much higher than that from CT scan and chest X-ray, the amount of radiation is within the range of the amount of radiation people can tolerate, and it does not have much effect on the human body. Enhanced CT requires injection of contrast agent, which may cause allergic reactions. Allergic reactions are classified as mild, moderate and severe, and the most serious ones may cause laryngeal edema, coma and shock, etc. Generally, people will not have any big reactions. If the patient’s kidney function is poor, the contrast agent will increase the damage to kidney function, so such patients can choose a contrast agent with less damage to kidney function, such as iodixanol, when doing enhanced CT. In addition, it is recommended that patients drink more water after the enhanced CT examination to facilitate the discharge of the contrast agent.