Hyperthyroidism | Diagnosis & Tests


How will my doctor know if I have hyperthyroidism?

If you have symptoms of an overactive thyroid, your doctor will check for an enlarged thyroid gland, rapid pulse, moist skin, eye changes and a slight tremor in your fingers or hand. The diagnosis can be confirmed with blood tests that measure the amount of thyroid hormone in your blood.

If your blood tests show an overactive thyroid, your doctor may do a thyroid scan to see if your entire thyroid is affected (which indicates Graves' disease) or if you have hyperfunctioning thyroid nodules or thyroiditis.

Your doctor may also do a radioactive iodine uptake test to measure your thyroid's ability to take up iodine. A high uptake of iodine means your thyroid gland may be producing too much hormone, which indicates Graves’ disease or a hyperfunctioning thyroid nodule. A low uptake of iodine indicates thyroiditis as the cause of your hyperthyroidism.


Hyperthyroidism: Diagnosis and Treatment by JR Reid, M.D., and SF Wheeler, M.D. (American Family Physician August 15, 2005, http://www.aafp.org/afp/20050815/623.html)

Written by familydoctor.org editorial staff

Reviewed/Updated: 03/14
Created: 08/05