• Thyroid Uptake and Scan

    (Thyroid Scintiscan; Technetium Thyroid Scan)


    A thyroid uptake and scan is a test that uses a radioactive substance and a scanning tool to evaluate the thyroid gland. The scanner picks up where and how much the radioactive substance was taken up by the thyroid. This helps determine the structure, location, size, and activity of the gland.

    Reasons for Test

    The scan may be ordered to:
    • Determine the cause of an overactive thyroid—hyperthyroidism
    • Test how well the thyroid is working
    • Determine if a thyroid nodule is functioning (if it is making thyroid hormone)
    Copyright © Nucleus Medical Media, Inc.

    Possible Complications

    Thyroid scans are associated with very few risks. Tell your doctor if you:
    • Have an allergy to medication or food, including iodine or shellfish
    • Are (or might be) pregnant or breastfeeding—the test could expose the baby to radiation
    • Take any medications on a regular basis—some can interfere with test results
    • If you recently had any CT scans, cardiac catheterizations, or other imaging tests that use contrast dye

    What to Expect

    Prior to Test

    • You may be asked to avoid certain food (containing iodine) or thyroid medication before the scan. Some can interfere with the results.
    • Jewelry, dentures, and other metallic objects will be removed.
    • You may be asked not to eat or drink anything after midnight.
    • Your doctor may order some tests to measure the amount of thyroid hormone in your blood.

    Description of Test

    You will be given a radioactive substance by mouth. Once the substance has had time to collect in the thyroid, the scan begins. You will lie on your back with your head tilted back. You will be asked to lie very still at certain times. A scanner will take pictures of your thyroid from different angles. The camera is not an x-ray machine. It does not expose you to more radiation. You may need to return to the radiology department after 24 hours for additional pictures.

    After Test

    You will be able to leave after the test is done.
    Because of the very low dose of radioactive substance used, the majority of the radioactive substance will leave your body in 1-2 days. You are not at risk for exposing other people to radiation. You can interact normally with them.

    How Long Will It Take?

    The scan itself takes about half an hour. The radioactive substance needs time to be absorbed before the scan. You may need to wait 4-6 hours if you take the substance by mouth.

    Will It Hurt?

    There is no pain associated with a thyroid scan. There may be times when you find it uncomfortable to lie still with your head tilted backward.


    The pictures of the scan take about an hour to develop. A radiologist will examine them. Based on the results of the test, further studies or treatment will be recommended.

    Call Your Doctor

    Call your doctor if you experience any unusual pain or discomfort.
    If you think you have an emergency, call for emergency medical services right away.


    American Thyroid Association http://www.thyroid.org

    Hormone Health Network—Endocrine Society http://www.hormone.org


    Public Health Agency of Canada http://www.phac-aspc.gc.ca

    The Thyroid Foundation of Canada http://www.thyroid.ca


    Hyperthyroidism. Johns Hopkins University website. Available at: http://www.hopkinsmedicine.org/healthlibrary/conditions/adult/endocrinology/hyperthyroidism%5F85,P00408. Accessed December 14, 2015.

    Hyperthyroidism and thyrotoxicosis. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T116479/Hyperthyroidism-and-thyrotoxicosis. Updated March 21, 2016. Accessed October 10, 2016.

    Thyroid nodule. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T115781/Thyroid-nodule. Updated December 11, 2015. Accessed October 10, 2016.

    Thyroid nodules. American Thyroid Association website. Available at: http://www.thyroid.org/thyroid-nodules. Accessed December 14, 2015.

    Thyroid scan and uptake. Radiological Society of North America Radiology Info website. Available at: http://www.radiologyinfo.org/en/info.cfm?pg=thyroiduptake. Updated March 28, 2013. Accessed December 14, 2015.

    Revision Information

  • LiveWell personal health survey

    How healthy are you really? Find out – free.Learn more

    It's time to stop guessing. If you want to make some changes but just aren't sure how, the free personal health survey from LiveWell is a great place to start.

  • HeartSHAPE Spotlight

    At risk for a heart attack? Learn more

    Fight heart disease and prevent heart attacks. HeartSHAPE® is a painless, non-invasive test that checks pictures of your heart for early-stage coronary disease.

  • Calories and Energy Needs

    Calorie NeedsLearn more

    How many calories do you need to eat each day to maintain your weight and fuel your physical activity? Enter a few of your stats into this calculator to find out.

  • Ideal Body Weight

    Ideal Body WeightLearn more

    Using body mass index as a reference, this calculator determines your ideal body weight range. All you need to do is enter your height.

  • Body Mass Index

    Body Mass IndexLearn more

    This tool considers your height and weight to assess your weight status.

  • Can we help answer your questions?

    Wellmont Nurse Connection is your resource for valuable health information any time, 24 hours a day, seven days a week. Speak to a Nurse any time, day or night, at (423) 723-6877 or toll-free at 1-877-230-NURSE.