How to Get a Thyroid Hormones Test

A thyroid hormone test measures the function of the thyroid. A doctor orders this blood test when he suspects a patient has an overactive, hyperthyroid, or underactive, hypothyroid condition. The thyroid releases hormones responsible for regulating metabolism and growth. A thyroid hormone test requires a blood draw to measure the levels of thyroid-stimulating hormone, TSH, Triiodothyronine, T3, and thyroxine, T4.

1. Document the symptoms you experience, it helps your doctor order the proper blood tests. Hypothyroidism can cause weight gain, fatigue, dry skin, and intolerance of cold. Hyperthyroidism has symptoms of rapid heart rate, weight loss, hot flashes and nervousness.


2. Schedule an appointment with your primary care physician. Explain your symptoms. Ask your doctor to run a thyroid hormone test to determine your TSH levels. Your doctor should perform a complete physical examination to rule out other medical conditions.


3. Have blood drawn in your doctor’s office or a designated laboratory. Inform the person drawing blood if you have had X-rays with iodine dye or medical tests with radioactive materials within the last six weeks. These can cause an inaccurate test result.


4. Sit in a chair while the nurse or phlebotomist wraps an elastic band around your upper arm. This stops the flow of blood and increases the size of the veins below the band. The nurse uses alcohol to clean around the needle site.


5. Remain still while the needle is inserted into the vein. Distract yourself by reading posters on the wall or making small talk with another person in the room. The person drawing the blood will attach a vial to the needle and fill it with blood.


6. The nurse removes the needle and elastic band once enough blood is retrieved. A gauze pad or needle pad stops any additional bleeding and covers the needle site. A laboratory analyzes the blood collected.


7. Wait for the results of your blood work. The results take approximately three days to return from the laboratory. Discuss the results with your doctor. Abnormal thyroid hormone levels require monitoring and medication. Inaccurate test results may occur in people taking medications such as corticosteroids, heparin, dopamine, methimazole and propylthiouracil. Long-term chronic illness and severe stress also adversely affect thyroid hormone tests.


8. Follow up with your doctor on a regular basis to monitor your response to thyroid hormone medications. Take medications as prescribed and report changes in symptoms to your doctor.