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Oral Contrast for Your Computed Tomography (CT) Scan

This information describes how to drink the oral contrast you need for your scheduled computed tomography (CT) scan. The contrast helps your doctor see an area better. 

Before Your CT Scan

When you arrive at the reception desk, a staff member will ask you if you are allergic to iodine or artificial sweetener. Depending on whether you have these allergies, we will give you one of the oral contrast solutions listed below. Both work the same way, are used for the same purpose, and are safe if you have diabetes. 

  • Iodine mixed with Crystal Light®, which contains aspartame. 
  • Diluted barium sweetened with saccharin, which does not have iodine.
You will start drinking the oral contrast 45 to 60 minutes before your CT scan. This will allow time for the solution to move into your bowels (intestines).

After Your CT Scan

  • Drink 2 to 3 (8-ounce) cups of liquid. Drinking liquids helps your body get rid of the contrast. 
  • If you have any questions about how to drink oral contrast, or other questions about your CT scan, talk with your healthcare provider.