Blood tests 40min after taking thyroid medication. How much will it affect its result?

[Gr8Nica]

Hi,

After waking up I took my current dose of Novothyral 75 (T4 93.75 & T3 18.75) and went to see my GP to request a new blood test. I got confused thinking I didn't take my meds yet and went to have a blood test soon after that appointment finished. When I got home I realized I did, in fact, took it and now wondering how much it will affect the result?

[SeasideSusie Remembering]

Gr8Nica

Hard to say. It's said that it peaks in the blood 2-6 hours after taking it, so 40 minutes may mean it hadn't yet made any difference. If it does affect the result it will give a false high FT4 and FT3.

[Gr8Nica in reply to SeasideSusie]

Thank you. Guess will have to wait and see...

[trelemorele]

Can you post your results once you have it, thanks

[Gr8Nica in reply to trelemorele]

TSH: 0.03 miu/L (0.3 - 4.2) - Abnormal, No Further Action

FT4: 13.3 pmol/L (9 - 23)

FT3: 6.1 pmol/L (2.5 - 5.7) - Borderline, No Further Action

trelemorele , SeasideSusie as the above numbers indicate it looks like those 40 mins could have had some impact on my results. I do not feel any overmedicated symptoms and actually based on those results wanted to further increase my dose hoping it will relive me from the remaining symptoms. I'll have to wait till the next blood test then.

[trelemorele in reply to Gr8Nica]

T3 starts raising 15 mins after ingestion and reaches pick about two hours after.

I need to find research paper with nice graph done on 50 mcg liothyronine in healthy patient and I'll post you link to that so you can see/investigate for yourself how it affects bloods - if you're interested of course.

Thanks for sharing, I needed it for my own blood tests fiddling purposes 😉

[Gr8Nica in reply to trelemorele]

That would be most helpful if you could. Thanks 😉

[trelemorele in reply to Gr8Nica]

Ahh so the nice graph I was taking about, I've done myself in Excel, based on the data from that paper.....

They have some basic graphs in the document not as visually pleasant but hey. The research paper is very informative.

I will have to think if I'm wanting to make my graph available online.... can't do it now as I'm at work and unfortunately can't attach to the message.

Link to the paper:

ncbi.nlm.nih.gov/pmc/articl...

[Gr8Nica in reply to trelemorele]

No worries, I can probably create my own. It shouldn't be too difficult. Than you.

I'm just disappointed based on inaccurate results I can't really raise my dose just yet.

[trelemorele in reply to Gr8Nica]

Uploaded now if you wanna have a look

dropbox.com/s/80vg9cduqo5qd...

[SlowDragon Administrator in reply to trelemorele]

Nice graph ....very useful 😀

[trelemorele in reply to SlowDragon]

Thank you 😊