T3 stands for Triiodothyronine.
What does T3 mean?
the active thyroid hormone that regulates metabolism
T3 stands for triiodothyronine, one of the two main thyroid hormones, the other being T4 (thyroxine). T3 is the more active form and has a strong effect on the bodys metabolism, influencing heart rate, temperature, and how energy is used. Most T3 is produced when the body converts T4 into T3 in the tissues. Blood tests may measure total or free T3, often alongside TSH and T4, to help assess thyroid function, particularly in hyperthyroidism.
When is T3 used?
T3 is measured in thyroid function testing, often when hyperthyroidism is suspected.
Frequently asked questions
What does T3 stand for?
T3 stands for triiodothyronine, the more active of the two main thyroid hormones.
What does T3 do?
It strongly affects metabolism, influencing heart rate, temperature, and how the body uses energy.
Where does T3 come from?
Most T3 is made when the body converts the other thyroid hormone, T4, into T3 in the tissues.
When is T3 measured?
It is often measured alongside TSH and T4, particularly when hyperthyroidism is suspected.