Re: Take T3 on day of FT3 test

[Guest guest]

Do NOT take it for 24 hours before hand.   Because T3 is so fast acting you are more likely to get a false result if taken on the same day.Why not ask the lab themselves.    When I was having a test I asked the particular lab and they told me not to take my thyroxine either.

It also does not go completely out of your system so you will be able to tell whether you are taking the right amount.    However the best test of all is how you feel.   Tests are just guides.   If your body is running well and you feel well then you are on the right amount.    There is always scope for adjusting to see whether you need more or less, provided it is done with a little at a time.

Lilian In view of why I'm doing the test would it be better for me to take it on the morning of the test, or not take it for 24 hours?  I'm not bothered about my GP thinking I'm taking too much ~ only to know where I am with it.

It would be really helpful to have some views on this please.

Thanks!

[Guest guest]

>

" Why not ask the lab themselves? "

Hi Lilian,

Thanks for your reply this is very useful. I did ask the lab I'm using but they

told me it depended what my doctor wanted to know by doing the test, and

basically refused to give me an answer!

Yes, I agree that how one feels is a very good guide ~ I'm not a straightforward

case though, as I'm hypersensitive to medications and can't ever take as much as

I need. The test will hopefully give me a better guide re where I am in

relation to T3.

Thanks again for your input.

Joanna

[Guest guest]

I did ask the lab I'm using but theytold me it depended what my doctor wanted to know by doing the test, andbasically refused to give me an answer!

Hello Joanna,

May I just add my 2 pence .... if you are taking both, T4 and T3 (whether synthetic or natural), then doing just an FT3 will not tell you very much, and the people at the lab were correct in saying that it depended on what you (or your doctor) wanted to know by doing this test. – T3 is used up constantly during the day as needed by the body and subsequently if you were doing the blood draw 24 hours later (without having taken any more meds) the FT3 figure would most likely be about half of what it would be had you taken your dose of T3 on the morning of the blood draw. Without seeing what the FT4 is doing at the same time as the FT3 it will be pretty much guess work as to whether you are taking too much or too little T3. ly, listening to your own body will give you a more accurate answer.

It really depends on what you want to find out from this single test and at what times of the day you usually take your T3. My guess would be that 24 hours after taking T3 you can expect about half or less of the figure you would get testing about 2 hours after ingestion.

My guess is based on my own TFT results – I take 2 grains NDT and supplement a little T3... most of the time about 6.25 mcg, sometimes 12.5 mcg, and I usually spread it throughout the day.....on the day before a blood draw however, I take only my morning NDT (1 grain) and a couple of hours later or so I take 6.25 mcg T3 to get me through the day without my second dose of NDT in the afternoon and then re-start taking my normal morning dosage straight after the blood draw. Doing it this way, my result consistently show a low-normal FT4 (which is to be expected when taking NDT) and my FT3 comes out bang in the middle of the ref range. If I were to take the last T3 dose in the afternoon, the figure would have been nearer to the top and if I had taken any T3 thereafter and closer to the time of the blood draw, the figure would have been at the top or well above the top respectively.....

Best wishes,

[Guest guest]

Hi Jo - if you are taking T3, it is easier to go by symptoms to

find out whether you are taking too much or too little. Too little and you will

be left with the symptoms of hyPOThyroidism - too much and you will be left

with the symptoms of hyPERThyroidism. After your last increase in whatever dose

of T3 you are taking, if you still suffer symptoms, add another half tablet of

T3 (either 10mcgs or 12.5mcgs depending on whether you are taking lyothyronine

or Cytomel) and stay on that dose for about 10 days, if symptoms still persist,

add another 10mcgs or 12.5mcgs. You keep increasing this way until the symptoms

HAVE disappeared.

If taking too much on the other hand, you will likely get

palpitations, feeling 'spaced out', hot, jittery, hyperactive and generally

YUK! If that happens, because you take T3 twice a day, don't take any more that

particular day and the day after, go back onto the dose you were on before you

took the last increase.

Serum thyroid function tests only show how much free T4 and free

T3 you have floating around in your blood - these tests do not show whether the

thyroid hormone is being used at cellular level.

Luv - Sheila

Hi,

My GP's lab refuses to do a Free T3 blood test for me and so I'm sending a

blood sample to a private lab instead.

I'm doing the test because I take T3 and I wish to know whether I'm taking too

much or too little.

In view of why I'm doing the test would it be better for me to take it on the

morning of the test, or not take it for 24 hours? I'm not bothered about my GP

thinking I'm taking too much ~ only to know where I am with it.