The thyroid-stimulating hormone (TSH) test measures the amount of TSH in the blood to convey how well a person’s thyroid functions. Normal levels are typically 0.4 to 4.0 milliunits per liter (mU/L) ...

Thyroid blood tests are an important part of diagnosing and treating thyroid disease. Based on how high or low the different values are—including key hormones such as TSH and T4—the lab can determine ...

Dear Dr. Roach: I’m a 72-year-old female. I was diagnosed 27 years ago with Graves’ disease, and was given radioactive iodine to kill my thyroid. I have been on levothyroxine since, and my blood work ...

Thyroxine (T4) is the main hormone your thyroid makes. Your thyroid hormones are important because they control how your body uses energy from the food you eat. (Photo Credit: iStock/Getty Images) T4 ...

If you're like most primary care clinicians, your email inbox is flooded with messages from patients with questions about lab results. A common query: Should I be worried about an abnormal value on a ...