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Computed Tomography Scan

Medically reviewed by Last updated on Oct 31, 2022.

What do I need to know about a computed tomography (CT) scan?

A CT scan uses x-rays to take pictures of your blood vessels, tissues, bones, or organs. It is also called a computerized axial tomography (CAT) scan.

How do I prepare for a CT scan?

Your healthcare provider will tell you which medicines to take or not take on the day of your CT scan. He or she may tell you not to eat or drink anything for 2 to 4 hours before your CT scan. Tell your provider if you know or think you are pregnant.

What will happen during a CT scan?

Your healthcare provider will ask you to lie on your back on a table. He or she may give you medicine to help you feel calm and relaxed. Contrast liquid may be used to help a body part show up better. The table will be moved into an open space in the middle of the machine. You will need to lie still during the CT scan.

What are the risks of a CT scan?

The contrast liquid may cause an allergic reaction. You may have a rash, itching, or trouble breathing. If you are pregnant, a CT scan may be harmful to your unborn baby. Contrast liquid may cause kidney problems that lead to kidney failure. The radiation from a CT scan may increase your risk for cancer.

Care Agreement

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.