Testing... testing : Hi everyone I'm just about... - Thyroid UK

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Testing... testing

maxart profile image
8 Replies

Hi everyone

I'm just about to get my second - ever set of tests done and have some questions:

1) I've been reading a lot and it seems that blood tests aren't necessarily reliable, sometimes due to slow circulation causing a concentration of hormone in the blood that gives a false result and sometimes due to the levels in the blood not being indicative of cellular uptake. My question is how we deal with this and how we know if this is the case

2) is there an optimal time to take blood and should it be fasting?

Thanks so much :) xx

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maxart
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Nanaedake profile image
Nanaedake

If you're having blood tests for a suspected thyroid condition you should have the test first thing in the morning, fasting and if you're taking thyroid medication you should not take it until after the blood test.

maxart profile image
maxart in reply to Nanaedake

Thanks - I'm hypo, on T3. First tests since starting meds.

Nanaedake profile image
Nanaedake in reply to maxart

I hope someone who takes T3 might respond. I think it's even more important with T3 to make sure you take it after blood test and not before as levels rise more rapidly than with LT4 (levothyroxine). Not sure how long you should leave between T3 dose and blood test though.

SeasideSusie profile image
SeasideSusieRemembering in reply to Nanaedake

12 hours between last dose of T3 and blood test :)

SeasideSusie profile image
SeasideSusieRemembering

To answer question 1 - a 24 hour urine thyroid test will show you how much hormone is being used.

maxart profile image
maxart in reply to SeasideSusie

Perfect. Thank you!!

ilenuca profile image
ilenuca

It s the first time i hear about this test. I dont think it s done in my country...

How much does it cost?

maxart profile image
maxart in reply to ilenuca

It appears to be from Genova Diagnostics Europe and costs £107 in U.K. Suggest you search online and see if you can get it where you are...

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