CT scans and other X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. CT scans provide low levels of radiation. During pregnancy, an abdominal CT scan is usually not recommended, because there is some evidence of risk to the fetus.

The most common dye used is iodine based. A person who is allergic to iodine may experience nausea, sneezing, vomiting, itching, or hives. Rarely, the dye may cause anaphylaxis (a life-threatening allergic response).