FT4 & TSH

A thyroxine test is a blood test that helps diagnose thyroid conditions. The thyroid is a small, butterfly-shaped gland at the base of your throat. Your thyroid makes hormones that control the way your body uses energy. These hormones affect your weight, heart, body temperature, muscle strength, and even your mood. In children, thyroid hormones affect growth, too.

TSH stands for thyroid stimulating hormone. A TSH test is a blood test that measures this hormone. TSH levels that are too high or too low may be a sign of a thyroid problem. The thyroid is a small, butterfly-shaped gland in the front of your neck. Your thyroid makes hormones that control how your body uses energy.