Low T4

[Peony57]

i forgot i had a blood test on morning of and took 2 grains of NDT 2 hours before blood test, my T4 levels came back at 4.9pmo/l ui have had a call from the doctor wanting to talk to me. can anyone please advise

thank you

[SeasideSusie Remembering]

Peony57

You say your FT4 is low but you haven't given a reference range, do you have this please?

What about TSH and FT3?

When on NDT it's essential to test FT3, that's the most important result.

[Peony57 in reply to SeasideSusie]

TSH 1.77 mIU/L. (0.27 - 4.2)

Free T3 4.8 pmo/L. (3.1 - 6.8)

T4 4.9pmo/L (12 - 22)

[SeasideSusie Remembering in reply to Peony57]

Peony57

Thank you.

Does your doctor know that you take NDT?

Which NDT are you taking?

When on NDT it tends to lower, even suppress, TSH and also tends to lower FT4. It's FT3 that is important and generally that would be in the upper part of it's range.

Did you take Biotin, or a B Complex containing Biotin in the 7 days before the test? Taking Biotin can give false results if Biotin is also used in the testing procedure, which most labs do. We don't know which way the results would be false.

Your TSH is telling us that you are undermedicated, as is your FT3.

Your FT4 is a puzzle, even though you appear to be undermedicated it would seem that there is very little T4 in your NDT, one would expect to see your FT4 somewhere around the lower end of it's range.

[Peony57 in reply to SeasideSusie]

thank you, yes they are aware i am taking NDT , interesting i have started Tru Thiroid which is new on the market in thailan this can only be the answer, and yes i was only taking 2 grains , so i will be in touch with manufacture and ask, but they did reassure me they were the same as Thyroid, I have not taken. any other supplements .

thank you for your reply, i really appreciate it

[SlowDragon Administrator]

Important to regularly retest vitamin d, folate, ferritin and B12 too, especially if under medicated as these results suggest you may be

What vitamin supplements are you currently taking