How To Prepare

Before the CT scan, tell your doctor if you:

• Are or might be pregnant.
• Are allergic to any medicines, including iodine dyes.
• Have a heart condition, such as heart failure.
• Have diabetes or take metformin (Glucophage) for your diabetes. You may have to adjust your medicine for a day before and after the test.
• Have had kidney problems.
• Have asthma.
• Have a medical device, such as a pacemaker or an insulin pump.
• Have had multiple myeloma.
• Become very nervous in small spaces. You need to lie still inside the CT scanner, so you may need a medicine (sedative) to help you relax.

Arrange for someone to take you home in case you get a medicine to help you relax (sedative) for the test.

Talk to your doctor about any concerns you have regarding the need for the test, its risks, or how it will be done. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).

How It Is Done

A CT scan is usually done by a radiology technologist. The pictures are usually read by a radiologist, who writes the report. Other doctors also may review a CT scan.

You may need to take off any jewelry, glasses, and hearing aids. Wear comfortable, loose-fitting clothes.

During the test, you will lie on a table that is attached to the CT scanner. Straps will hold your head still but your face will not be covered.

The table slides into the round opening of the scanner, and the scanner moves around your body. The table will move while the scanner takes pictures. You may hear a click or buzz as the table and scanner move. It is very important to lie still during the test.

During the test, you may be alone in the scan room. But the technologist will watch you through a window. You will be able to talk to the technologist through a two-way intercom.

The test will take about 30 to 60 minutes. Most of this time is spent getting ready for the scan. The actual scan only takes a few seconds.

How It Feels

The test will not cause pain. The table you lie on may feel hard, and the room may be cool. It may be hard to lie still during the test.

Some people feel nervous inside the CT scanner.

If a medicine to help you relax (sedative) or dye (contrast material) is used, an IV is usually put in your hand or arm. You may feel a quick sting or pinch when the IV is started. The dye may make you feel warm and flushed and give you a metallic taste in your mouth. Some people feel sick to their stomach or get a headache. Tell the technologist or your doctor how you are feeling.