How do you diagnose an overactive thyroid?

A diagnosis can be confirmed with blood tests that measure the levels of thyroxine and TSH in your blood. High levels of thyroxine and low or nonexistent amounts of TSH indicate an overactive thyroid. The amount of TSH is important because it's the hormone that signals your thyroid gland to produce more thyroxine. read more

Hyperthyroidism and Graves’ Disease. The most common cause of hyperthyroidism is an immune system disorder called Graves’ disease. It’s more likely to affect women under the age of 40. In addition to the other symptoms of hyperthyroidism, about 30% of people with Graves’ disease develop a condition called Graves’ ophthalmopathy. read more

Thus, the diagnosis of hyperthyroidism is nearly always associated with a low (suppressed) TSH level. If the TSH levels are not low, then other tests must be run. Thyroid hormones themselves (T3, T4) will be increased. For a patient to have hyperthyroidism, they must have high thyroid hormone levels. read more

The time needed for the procedure may vary, depending on how long it takes the isotope to reach your thyroid gland. You may have some neck discomfort with this test, and you'll be exposed to a small amount of radiation. Sometimes you may have a thyroid scan as part of a radioactive iodine uptake test. read more