Hi
My daughter takes T3 only and because she is not feeling too good lately wants to test her levels.
I understand that when on T3 only then TSH will be suppressed and FT4 will be low, so is it pointless to get the test that checks TSH, FT4 and FT3 or should we just purchase the FT3 only test.
Many thanks.
Probably safer to test all three
She really needs vitamin D, folate, ferritin and B12 tested too
Thank you, she is getting a biochemical test at the Doctors soon so will that cover the Vitamin D, folate, ferritin and B12 ? and they will probably do TSH.
I'm on T3 only and have been for many years. As you suspect, testing TSH and FT4 on this regime is a pointless expense. Paul Robinson has written about why this is the case in several blog posts on his website, so you could have a look at the relevant ones (assuming you haven't already):
Many thanks for your reply.
I have read some of Paul Robinsons articles but will take a look at the link, many thanks for it.
My daughter takes her T3 all in one dose early morning, but I have read it is advisable to leave 12 hours from last does to testing, is this what you do ?
Yes that's what I do, although I don't often test now.
Hi
the day before the test do you take your dose on the evening, instead of in the morning ?
I had to think about this because it's been a while! I think last time I took around week or two gradually moving my single large morning dose forward, so that I could leave 12 hours before the draw. It really affected how I felt, but I had to carefully adjust again after the draw over a similar period of time.
The result was way above range, which I expected, because I have a form of TH resistance - hence the large once-a-day dose. I prefer to monitor my vitals instead. For me, that's much more useful, but it depends really on the individual's specific dose and the reason why they need T3 monotherapy in the first place.
FT3 
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Blood Test ft3 ft4 TSH - Round 2
Testing Costs
TSH, FT4 & FT3 normal! (?)
