The Total T3 indicates the total amount of serum T3. Most of that is tied up with protein molecules which makes it biologically inactive. Free T3 is the small portion of Total T3, that is biologically active. Scientific studies have shown that Free T3 correlated best with hypo symptoms, while Free T4 and TSH did not correlate at all. So, Total T3 is an indicator of T3 levels, but not nearly as useful in assessing thyroid status as Free T3. If the doctor resists, just insist that you want Free T3, not Total T3.
This is another good link for your doctor. It is a letter written by a good thyroid doctor for patients that he sometimes consults with after an initial evaluation and tests. The letter is then sent to the participating PCP of the patient to help guide treatment. In the letter, please note the statement that, "The ultimate criterion for dose adjustment must always be the clinical response."
http://hormonerestoration.com/files/ThyroidPMD.pdf
Thank you, thank you, thank you!! I thought an Endo would be aware of the TSH value or lack there of, however, I sadly am wrong. I am going to try and get her to order a FT3 test, as she only ordered a Ft4. Do you know if TOTAL T3 has any value whatsoever?? I am going to continue taking my 120mg and hope that the information you provided to me will at least give her an open mind as to not putting such emphasis on my TSH level. I appreciate your help!
Many doctors have never learned or accepted that TSH is often suppressed below the reference range before hypo patients can get their Free T3 and Free T4 levels high enough in the ranges to relieve symptoms. They have been mistakenly taught that a TSH below range automatically makes you hyperthyroid. Wrong. You are hyper only when having hyper symptoms due to excessive levels of Free T3 and Free T4, which you don't have.
So you should always make sure that they are testing you for both Free T3 and Free T4 each time you go for new tests. Also, you should resist letting the doctor reduce your mes, unless you are having hyper symptoms. You might impress your doctor with this scientific study that concludes, "Serum TSH concentrations, as determined by an immunoradiometric assay, varied from less than 0.02 to 11.9 mU/l in treated hypothyroid patients; 21 patients (42%) had values outside the reference limits. As a single test, serum TSH is therefore not very useful for the assessment of adequate thyroxine dosage in patients with primary hypothyroidism."
http://www.ncbi.nlm.nih.gov/pubmed/3687325
Also, here's another bit of useful info on this subject.
"We consider that biochemical tests of thyroid function are of
little, if any, value clinically in patients receiving thyroxine
replacement. Most patients are rendered euthyroid by a daily dose
of 100 or 150 ,tg of thyroxine. Further adjustments to the dose
should be made according to the patient's clinical response."
This was taken from the following link.
http://www.ncbi.nlm.nih.gov/pubmed/3687325
There are many such references about TSH being a poor diagnostic, expecially after taking thyroid meds.