What should I expect before a CT scan?

Most CT scans are conducted as an outpatient procedure. A patient can have a CT scan done in a hospital or an outpatient facility. CT scans are painless and, with the exceptions of those done in emergency situations, patients can have the test and then go home.

You may be asked not to eat or drink anything for several hours before the test. You should inform your physician of any medications you are taking and if you have any allergies. If you have a known allergy to contrast material, or "dye," your doctor may prescribe medications to reduce the risk of an allergic reaction.



Most places performing the test will ask you a series of questions about your health. Inform them and/or your doctor of any recent illnesses or other medical conditions, and if you have a history of heart disease, asthma, diabetes, kidney disease or thyroid problems. Women should always inform their physician and the CT technologist if there is any possibility that they are pregnant.

If you are claustrophobic, your doctor may prescribe a sedative to help calm you. If an infant or toddler is having a CT scan, the doctor may give the child a sedative to keep them calm and/or still.

Preparing for a CT scan largely depends on which part of the body will be scanned. You should wear comfortable, loose-fitting clothing to your exam. In some instances, you may be asked to remove your clothing and wear a hospital gown. Since x-rays travel easily through fabric, you may be able to wear your underwear for these cases.

However most places let you wear what you have on as long as you remove any metal objects, such as jewelry, that might interfere with image results. You may also be asked to remove hearing aids and removable dental work.

A contrast material is needed for some CT scans, (not all) to help highlight the areas that need to be examined. This contrast material actually blocks the X-rays and appears white on your final images. Contrast material can be introduced into your body in a variety of ways.

Oral Contrast. If your esophagus or stomach is being scanned, you may need to swallow a drink containing contrast material. This drink may taste unpleasant and in some cases cause diarrhea later.

Injection of a Contrast. Contrast agents can be injected into an intravenous line, to help view your gallbladder, urinary tract, liver or blood vessels. Some people experience a feeling of warmth during the injection, or a metallic taste in their mouth. This is common.

Rectal Contrast. A barium enema is a type of contrast material used to help visualize the intestines. It can make a patient feel bloated and slightly uncomfortable.

Finally, you should arrange for someone to take you home after the test in case you get any medicine to help you relax.

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