Reverse T3 can be used to evaluate individuals with low T3, and to evaluate metabolism and thyroid function.
Acute diseases are known to alter thyroid hormones T3, T4 and TSH activity by production of a hormone Reverse T3 somewhere else in the body. It lowers levels of T3 to help adapt to illness.
No special preparation is necessary prior to blood sample collection.
Diagnosing and monitoring treatment of sick euthyroid syndrome.