*** edited to add FT3 was 3.20. (Range 2.30-4.20).
Doctor did bloods for another issue but TSH & T4 were on there.
TSH 0.06 (range 0.55-4.78), so I know being on NDT this low is fine
FT4 0.31 (range 0.89-1.76) so am way below range and believe it should be mid range.
I take NDT(S-Thyroid) x 1 per day and T3 x 1 per day.
Why would my T4 be running so low, what can I do to get it up? Both are flagged on my results for when I go back next week so will have to explain what I am taking.
Hi geminichic
It may be of more help to people if you put down exactly what your dose is. You mention NDT x 1 and t3 x 1 but you don’t specify actual dose. If you can clarify people will be able to comment x.
I’m in work so don’t have in front of me. Whatever the standard dosages are...... 25mg comes to mind but not sure
When you get home have a look and post the doses.
You also don’t appear to have a t3 result on your post and as your taking t3 you really need to know what that is too in order to be able to work out what you need to do.
Are you feeling symptoms of being undermedicated or not?
As I mentioned in my post, these tests were for another health issue so I didn’t know she was testing them. Last time T3 was good. I feel as always tired but not as bad as I can often feel when not on them!
Well I think SeasideSusie has given you a far better answer than I could of 😊
Geminichica
When taking NDT or T3 this tends to lower the FT4 level as well as TSH.
You are taking 1 x Thyroid-S which contains 38mcg T4 and 9mcg T3 plus 1 x T3 which is either 20 or 25mcg if taking a full tablet.
So your total hormone dose is 38mcg T4 plus 29 or 34mcg T3.
Your FT4 is low because of the very low dose of T4 plus the effect of the T3 lowering FT4.
When taking NDT and/or T3 it is essential to test FT3 as well as TSH and FT4. FT3 is the most important result.
When taking NDT it doesn't necessarily mean that you have to have FT4 mid-range, we are all different with our needs, some people are best with FT4 mid-range, some are happy with it lower, some may need it higher, it's up to us to find our sweet spot by experimenting with dose and making small changes gradually.
Ok thank you! As mentioned in my post she was testing me for another health issue and these were just on there. When I go for thyroid I make sure to have T3 done also. Last time it was good.
Have edited my post to now add the T3.
Geminichica
I can't see an T3 result there, your post is still showing only TSH and T4.
What is important with thyroid tests, and I realise this was a surprise test you weren't prepared for, is that:
* TSH, FT4 and FT3 are all done at the same time and from the same blood draw. Was your T3 test done with the others?
* That it's Free T4 and Free T3 are tested, not Total T4 and Total T3, can you confirm which yours are.
* Last dose of NDT/T3 should be 8-12 hours before the blood test, can you confirm what time your last doses were.
Sorry it must not have saved. All where done at the same time, I’m guessing the must hold the samples or something. FT3 was 3.20 (range 2.30-4.20), T4 was also free T4. I did not take my thyroid meds the morning of the bloods, so would have been taken about 22 hours previously.
Geminichica
TSH 0.06 (range 0.55-4.78)
FT4 0.31 (range 0.89-1.76)
FT3 was 3.20 (range 2.30-4.20)
I did not take my thyroid meds the morning of the bloods, so would have been taken about 22 hours previously.
As you took your NDT 22 hours before the test, the FT4 andFT3 are showing as false lows.
Your FT3 is showing as 45% through range, we don't know how much higher it would be if NDT taken at the correct time but I would expect it to have been over half way through range, whether your FT4 would be in range nobody knows.
You ask what can you do to get it up but you haven't said how you feel. Do you need it higher?
If you are symptomatic I think it might be a good idea to do another test with the proper timing of last dose of NDT (adjust time and split dose the day before it necessary) to give an accurate measure of your levels. You can then decide if it's more NDT you need or whether you might benefit from the addition of some Levo to bring your FT4 up.
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