Hyperthyroidism (Overactive Thyroid)

The diagnostic process for hyperthyroidism may involve multiple steps, including:

• A physical exam: To start, your healthcare provider will do a physical exam to check for signs of hyperthyroidism, like an enlarged thyroid, rapid heart rate and warm, moist skin.
• Thyroid blood tests: Blood tests can check your thyroid hormone levels. When you have hyperthyroidism, levels of the thyroid hormones T3 and T4 are above normal and thyroid-stimulating hormone (TSH) is often (but not always) lower than normal.
• Thyroid antibody blood test: This test can check if Graves’ disease is the cause.
• Imaging tests: Various imaging tests of your thyroid can help diagnose hyperthyroidism and its cause. They include a radioactive iodine uptake (RAIU) test and scan and a thyroid ultrasound. Your provider will go over the options and processes with you and recommend the test they think is best.