Timing of Thyroid blood tests

[cazza1001]

I stupidly took my thyroid meds 3 hours before my bloods ( 150 levo and 20mcg of Liothyronine) - I've ended up over range on my T3 at 7.3 - upper limit is 6.8 ! This has never happened in the last 3 years but I've never taken meds on the day before my bloods.

Doctor wants me off T3 now ... ( I source from Europe with a private script from my old GP - this one not so keen ). I tried to explain that I had taken meds on the day but he said you are supposed to take them on the day! I had totally forgotten why they skew the results if taken on the day ? Any science I can throw at him would be welcome .... TIA

[jimh111]

ncbi.nlm.nih.gov/pmc/articl... . Note the people in this trial took 50 mcg L-T3 and were not hypothyroid, i.e. didn't need thyroid supplements. Also, note the minimal effect on heart rate, other than having lunch or dinner - but he took your pulse didn't he ;-).

You can print this paper off and throw it at him, a better option would be to find a leather bound volume of this journal and throw that at him!

[cazza1001 in reply to jimh111]

thank you so much

[Lalatoot]

Some doctors want thyroid meds taken partic t3 taken 2 to 4 hours prior to test. This is so they can measure the effects of t3 at their peak. If your gp is clued up he will argue that your peak level which was measured was over range.

My previous endo was of this mindset and instructed me to do this. Of course I didn't! 😊

[shaws]

The fact that doctors have absolutely no idea that a blood test taken shortly after tablets of thyroid hormones are swallowed give a 'wrong' result. Ignore what he states.

Ask him to give another test and make sure you leave the proper gap and take T3 after the test, not before.

The day before a blood draw is taken, put your T3 in another place from the usual one, so you aren't in 'automatic mode' the day before a test is due - that will also act as a reminder.

[cazza1001 in reply to shaws]

that is so helpful - I did remember the night before but not on the day !! thank you

[jimh111 in reply to shaws]

In it's place put a note of where you've put your L-T3 in case you completely forget where you put them!!!

[pennyannie]

Hey there

I guess you could cover yourself by writing to your file, through your doctor, apologising for your error and rather than request a rerun of your thyroid blood test, you undertook this yourself, and enclose a private copy of an " in range T3. " to save the NHS additional expense.