Nuclear Medicine - Medical Imaging - St. Michael's Hospital

Programs & Services - Medical Imaging

This procedure treats hyperactive thyroid glands.

Many medications interfere with the results of this test. Please talk to your doctor about which medications to stop for this test and when to stop taking them.
Products high in iodine should not be eaten for one week before the test and until the test is complete. Excessive iodine in the body falsely lowers the results of this test. Do not eat or drink products that contain shellfish (lobster, crab, shrimp, etc), kelp products or supplements, or cough medicines for at least one week.
You should have no X-ray tests that use an iodine-based contrast dye within two to four weeks of this test.
Bring a list of all medications and supplements you take. This includes vitamins, herbal remedies, and holistic medications.
Do not bring children or pregnant women with you to the department. We do not want to expose them to unnecessary radiation.
Any of these procedures is subject to change according to the nuclear medicine physician. The duration of the tests is a rough estimate. Please be aware that the time may be lengthened if a scan has to be repeated, if emergency cases are brought to the department or due to unforeseen circumstances.

The procedure takes about 15 minutes.
A technologist will briefly explain the test to you and try to answer any questions you may have about the procedure.
A technologist will ask you a few questions about your medical history and medications.
Your doctor will give you a radioactive iodine therapy drink to decrease the activity of your thyroid gland based on his or her calculations.
The drink itself is colorless, and it is tasteless.