FT3 Free triiodothyronine Thyroid
The FT3 (free triiodothyronine) test is a blood test that measures the amount of free circulating T3 hormone in the body. FT3 is the active thyroid hormone that plays an important role in metabolism, energy metabolism and temperature regulation. This test is of value in detecting thyroid disorders such as hyperthyroidism or to assess the effectiveness of thyroid treatment.
In the body, most of the thyroid hormones (T4 and T3) are bound to proteins in the blood. Only the free (unbound) part is biologically active and available to the body. FT3 stands for "Free T3" or free triiodothyronine.
This blood test consists of:
- FT3 (free triiodothyronine) - method: electrochemiluminescence immunoassay (ECLIA)
Reference values are between 2.63 and 5.71 pmol/L. A value that is too high or too low may indicate a disturbance in thyroid function. If desired, the value can be converted using the factor: pg/ml x 1.54 = pmol/L.
This test is particularly suitable for people with symptoms of a thyroid gland that works too fast or too slow, such as fatigue, weight changes, hair loss, palpitations or mood swings. FT3 provides additional information to the FT4 and TSH determinations.
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