Summary
Your thyroid is a butterfly-shaped gland in your neck, just above your collarbone. It is one of your endocrine glands, which make hormones. Thyroid hormones control the rate of many activities in your body. They include how fast you burn calories and how fast your heart beats. Thyroid tests check how well your thyroid is working. They are also used to diagnose and help find the cause of thyroid diseases such as hyperthyroidism and hypothyroidism. Thyroid tests include blood tests and imaging tests.
Blood tests for your thyroid include
- TSH - measures thyroid-stimulating hormone. It is the most accurate measure of thyroid activity.
- T3 and T4 - measure different thyroid hormones.
- TSI - measures thyroid-stimulating immunoglobulin.
- Antithyroid antibody test - measures antibodies (markers in the blood).
Imaging tests include CT scans, ultrasound, and nuclear medicine tests. One type of nuclear medicine test is the thyroid scan. It uses small amounts of radioactive material to create a picture of the thyroid, showing its size, shape, and position. It can help find the cause of hyperthyroidism and check for thyroid nodules (lumps in the thyroid). Another nuclear test is the radioactive iodine uptake test, or thyroid uptake test. It checks how well your thyroid is working and can help find the cause of hyperthyroidism.
NIH: National Institute of Diabetes and Digestive and Kidney Diseases
Resources
- Free T4 (Thyroxine) Test (American Association for Clinical Chemistry)
- T3 (Triiodothyronine) Test (American Association for Clinical Chemistry)
- Thyroid Antibodies (American Association for Clinical Chemistry)
- Thyroid Diseases Tests (American Association for Clinical Chemistry)
- Thyroid Function Tests (American Thyroid Association) Also in Spanish
-
Thyroid Scan and Uptake
(American College of Radiology, Radiological Society of North America)
Also in Spanish
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Thyroid Tests
(National Institute of Diabetes and Digestive and Kidney Diseases)
- TSH (Thyroid-Stimulating Hormone) Test (American Association for Clinical Chemistry)
- Ultrasound of the Thyroid Gland (American College of Radiology, Radiological Society of North America) Also in Spanish
Clinical Trials
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ClinicalTrials.gov: Thyroid Function Tests
(National Institutes of Health)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
Patient Handouts
- Antithyroglobulin antibody (Medical Encyclopedia) Also in Spanish
- Antithyroid microsomal antibody (Medical Encyclopedia) Also in Spanish
- Fine needle aspiration of the thyroid (Medical Encyclopedia) Also in Spanish
- Radioactive iodine uptake (Medical Encyclopedia) Also in Spanish
- T3 test (Medical Encyclopedia) Also in Spanish
- T3RU test (Medical Encyclopedia) Also in Spanish
- T4 test (Medical Encyclopedia) Also in Spanish
- TBG - blood test (Medical Encyclopedia) Also in Spanish
- Thyroid scan (Medical Encyclopedia) Also in Spanish
- Thyroid ultrasound (Medical Encyclopedia) Also in Spanish
- TSH test (Medical Encyclopedia) Also in Spanish
- TSI (Medical Encyclopedia) Also in Spanish