Thyroid scans

thyroid scan

The thyroid is a gland in the neck that produces chemicals that tell the body how to use energy. A thyroid scan is performed to determine how well the thyroid is functioning. You will be given a capsule of radioactive material to take by mouth prior to the test.

This material or “tracer” is absorbed in the thyroid gland. The test measures the amount of “tracer” absorbed and how quickly it is absorbed to determine if your thyroid is functioning properly.

How to prepare

  • Do not take any thyroid hormones for at least 14 days prior to the scan.
  • Do not take any anti-thyroid medication for at least 7 days prior to the scan.
  • Stop taking vitamins and sinus or cold medicine 3 days before the scan
  • Do not have any x-ray studies that require an IV contrast for four to six weeks prior to your scan.

What to expect

When you arrive at the nuclear medicine department at the Imaging Center, you will receive a capsule of radioactive material or “tracer” to take by mouth. You will be asked to return in 4 hours for the scan. Some patients are also asked to return again in 24 hours for a second scan. This is determined by your doctor. Each scan takes approximately 30-45 minutes. You will be placed on your back while three, ten-minute images are scanned and acquired.

What happens to the radioactive material?

Most of the radioactive material will be eliminated in your urine or stool. The rest will simply disappear over a brief period of time.


You can resume your normal activities immediately after the test.


A doctor who has specialized training in nuclear medicine will interpret the images. A report will be dictated and sent to your doctor. It usually takes 1-2 days for your physician to receive the results.

Contact your doctor’s office for results.