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Low Free T4?

Went to the doctor with all the classic symptoms of hypo and doc had bloodwork done. I requested free t3 and t4 in addition to some that the doc ran. Nurse called and said results came back and everything was normal but upon receiving paperwork for the results my TSH was normal 1.647 mlu/mL (0.350-4.670) Free T3 was normal 318.63 pg/dl (320.00-420.00) but Free T4 was low 0.87 ng/dl (0.89-1.76) Is this representative of anything considering my symptoms or are these numbers still normal?
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Avatar universal
Hi there! If what you wrote is correct, your Free T3 is below the range as well. So with that and the too low T4 and your clinical symptoms I can't understand how your doctor can say everything is normal.

Even if your T3 is within the range (but low?) if your T4 is below the range everything is definitely not normal, especially she you're having symptoms.

I would look for another doctor, a thyroid specialist. You sound hypo and need medication to feel better. You should also do antibody testing.

Good luck and don't give up!
Avatar universal
Your Free T3 and Free T4 are much too low in the range and, for many people, consistent with having hypothyroid symptoms.  The ranges are not functional across their entire breadth, due to the erroneous method used to establish them.  Many members say that relief from hypo symptoms required Free T3 in the upper part of its range and Free T4 at least at the middle of its range.  

A good thyroid doctor will treat a hypo patient clinically by testing and adjusting Free T3 and Free T4 as necessary to relieve symptoms, without being constrained by resultant TSH levels.  You can get some good insight into clinical treatment from this letter written by a good thyroid doctor for patients that he sometimes consults with after initial tests and evaluation.  The letter is then sent to the participating doctor of the patient to help guide treatment.  In the letter, please note the statement, "the ultimate
criterion for dose adjustment must always be the clinical response of the patient."

Avatar universal
Soory! typo I meant 230-420
Avatar universal
I dont have another appointment with this doctor for another two months, but the doc seems sure I do not have a hypo problem, should I attempt to see another family md? I do not think there are any thyroid docs in my area accepting new patients.
Avatar universal
With your description of having typical hypo symptoms, and with your lab results, I'd say you are hypothyroid.  Your attendant low TSH only suggests that there may be a hypothalamus/pituitary issue and there is insufficient stimulation of the thyroid gland by TSH.    

For further assurance, in the words of a good thyroid doctor, ""The free T3 is not as helpful in untreated persons as the free T4 because in the light of a rather low FT4 the body will convert more T4 to T3 to maintain thyroid effect as well as is possible. So the person with a rather low FT4 and high-in-range FT3 may still be hypothyroid. However, if the FT4 is below 1.3 and the FT3 is also rather low, say below 3.4 (range 2 to 4.4 at LabCorp) then its likely that hypothyroidism is the cause of a person's symptoms."

Rather than wait around for the appointment, I think I would call and tell the doctor tht you are suspicious of having central hypothyroidism, thus the TSH remains in range, but your Free T4 and Free T3 are too low to prevent hypo symptoms that you have.   Then you can ask for a therapeutic trial of thyroid med to determine the effect on how you feel.  

In case this doesn't work, and you need a good thyroid doctor, please tell us your location and perhaps we can suggest a doctor for you.  

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