T3.. Taken at 5am, blood test 11.30🤔 - Thyroid UK

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T3.. Taken at 5am, blood test 11.30🤔

birkie profile image
14 Replies

Hi everyone ❤️

Just wondering about what the endo in Liverpool was talking about in relation to my blood work on the 8th of August :

History.. I took my T3 10mg at 5am(I normally take it at 8am but we're travelling to Liverpool so took 10mg at 5am) I was not under the impression the endo was going to take a thyroid pannle as I was only there for.. PTH, Calcium, vitamin D.

However she did request it on the form for which I had no knowledge of, if I'd known I'd have stated I'd taken 10mg at 5am.

When the endo rang yesterday (I posted what was said) she noted I was over medicating myself as my T3 was (11.4) and my TSH was( 0.05).. I went on to explain I'd taken my 10mg at 5am.

She went on to explain the hours past which were (6) since taking the medication (T3)

She asked when my next tablet would be due I said 1pm but I've not brought them as I'm having gut issues, but she said your T3 was (11.4) at 11.15 time of blood draw!

So in another 1 hour 45 mins you would be taking another 10mg... "Yes I said, then at 6.30 I take 5mg.. 25mg" in total, but I'm struggling with 25mg due to gut issues.

As I posted yesterday she thinks I'm hypersensitive to the drug saying it looks like it's getting into my system fast, she as asked me to decrease to 20mg until we speak in 2 weeks time.

But I'd like to ask...

1,how fast does T3 usually get into your system?

2, how long would it last in the system?

3, showing results after 6 hour 15 mins.. a T3 of 11..4 and a TSH of 0.05) just taking 10mg does this sound right? as I'd be taking another 10mg in 1 hour 45mins🤷‍♀️

My bloods on 25mg (for which I struggled tremendously 🤮) were... T3... 5.4..TSH..1.77) took last 5mg at 6.30pm.

Can anyone shed any light on this? 🤔

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birkie
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14 Replies
tattybogle profile image
tattybogle

Testing 15hrs after 5mcg T3 is obviously going to show a relatively lower result compared to the levels you actually have for most of the daytime.

if you usually take 10mcg at 5am and and another 10mcg at 1pm ... and we now know that 6 hrs after taking 10mcg you still have very over range fT3, then this means you are spending at least 12 hrs a day every day with fT3 very over range .

The endo has worked this out now . It is clear that testing as you usually do is not giving a realistic impression of how high your fT3 levels are for 50% of the day.

you can expect her to lower your dose . realistically she doesn't have a lot of choice now even if she did personally agree that fT3 needs to be allowed to go over range for a short while in some patients .

The Liothyronine guidelines that endocrinologists work to do not allow them to condone patients having such over range fT3 levels ... if you want/ need to medicate at that level you have to make sure you don't give them any evidence of it happening .

unfortunately you just did.

birkie profile image
birkie in reply to tattybogle

She's really no going to take me off the t3, I was there to see her because of my parathyroid glands showing over activity, but as I said she popped a thyroid blood test in.She thinks I'm hypersensitive to it, and as decrease me to 20mg

But your right in what you said about me having my last does of 5mg at 6.30pm...maby if I'd taken it later the result would have been higher.. It was 5.4 (T3 level) TSH 1.77 taken last 5mg at 6.30pm.

We are going to discuss my parathyroid issue, but she also wants to discuss the T3, I have told her I'm not willing to go back on T4 as it never restored my T3 level, only T3 as done that!

I'm rather hoping she prescribes NDT,... I can only hope.. Or she may just see my levels on 20mg, but even on this I still have gut issues 🤮

Thanks for the info tattybogle 💓

tattybogle profile image
tattybogle in reply to birkie

Top graph , top line ....... shows how fT3 level changes in the hours following a dose.

a very sharp rise after approx an hour ,

a sustained peak for 2 /3 hrs ,

then a sharp fall ,

and back to base level by approx 8 hrs .

hence the forum recommendation to test 8-12 hrs from last dose.. because it misses the highest point of the peak , and it also misses the periods of time when levels are changing very rapidly.

individuals will very in quite how fast the highest level is reached ... eg those with poor gut absorption may take longer than an hour to get to the peak ... and consequently they will still have the highest levels past 4/5 hrs ... this may explain why you still have such very high levels at 6 hrs ... ie. it may be taking a bit longer to get into your blood than the person in this graph , and therefore it will be later when it starts to go down again.

if you increase the size of the last dose (10mcg ) , the peak would be higher up the graph

if you reduce the size of the last dose (5mcg) , the peak will be lower down on the graph ,

But (i think) the time taken for the peak to rise and to lower again would be the same regardless of taking 5mcg or 10mcg .

you have been showing GP a lower level of fT3 than you have at any point during a normal day .... you are showing them 15 hrs after just 5mcg, but by the time of your 9am test, you would normally have had another 10mcg .. so you don't really have fT3 levels quite as low as the ones you are showing the GP .....on a normal day your levels for most of the day are much higher than that. and this explains why whenever they test you unexpectedly, they are getting much higher fT3 levels.

you have now shown the endo something that is close to the highest level of fT3 you have at any point in the day . ( note , it may have been even higher if you tested 3/4/5 hrs after dose)

Some endo choose to test at 3 hours post dose deliberately , to see how high the highest point is, because that is what some of them want to know.

..
birkie profile image
birkie in reply to tattybogle

Thank you tattybogle 💓

Just note.. I only did the 5am meds because I was travelling to Liverpool.. I normally take the 10mg at 8am...then 10mg 3pm..then 5mg 6.30pm

I normally just take the 5mg at 6.30pm then go to my surgery for the blood test at 8.45/9am...so maby that's why it showed a T3 level of 5.4...it could have been higher if I'd done the 10 hour ,if you get my meaning, I'm maby leaving to big a gap between the last dose and the test to get the correct reading.

And I'm having bad gut issues with the drug T3 ,but also had same issues with T4, so as you say maby that's playing a part to👍

tattybogle profile image
tattybogle in reply to birkie

yes well if you'd taken it at 8 am the fT3 result would probably have been even higher , endo would have had a fit.

"I'm maby leaving to big a gap between the last dose and the test to get the correct reading".

yes , and you are only taking 5mcg for that last dose,.... Both these factors are what gives you an 'in range' fT3 level.

but , in my opinion it's a bit unrealistic to test that way , ... it doesn't show what levels you usually have available in your blood for most of every day.

it would give a more realistic idea of your average fT3 levels on 25mcg to take half the daily dose no more than 8-12 hrs before a test.

I understand why you're testing the way you do , to get in range results to keep your prescription.... but if you're doing that ,then you can't risk going anywhere near a needle when you've taken a dose within the previous 8 -12 hrs

in future ,you need to expect any endo / phlebotomist will always test your thyroid bloods , even if you are seeing them for something else. Your GP will most likely have informed endo of some concerns re. overmedication when they referred you. because GP has also seen some very high fT3 results when you weren't expecting blood tests , so actually i'd have been astonished if endo didn't test your thyroid at this appointment

Oldie68 profile image
Oldie68 in reply to tattybogle

Could you please provide a reference? Arte the plots from an article or a book?

tattybogle profile image
tattybogle in reply to Oldie68

Oldie .. for more details / references/ other graphs/ etc , please see replies to this post :

healthunlocked.com/thyroidu... suggested-thyroid-hormone-test-timing-protocols

Vvap profile image
Vvap in reply to birkie

You are talking about your T3 doses in mg(milligrams). Do you mean that or do you mean mcg(micrograms).?

birkie profile image
birkie in reply to Vvap

Micrograms... 10 micrograms at 8am..10mg at 3pm then 5mg at 6.30...the endo as now decrease me to 20mg split 10mg..10mg..until I speak to her in 2 weeks.But I'm not under this endo for my thyroid, I'm with her because my parathyroid glands have gone over active, 3 parathyroid glands have lit up on pet scan, so waiting for her to sort that out.

But she as taken an interest in my thyroid levels to (no thyroid)

At least someone is listening to me because no one else in my surgery was👍

DippyDame profile image
DippyDame

Forgive me if I'm a tad confused here  birkie but...

You took 10mcg T3 at 5am...

The blood draw was at 11.15am....a gap of 6 hrs 15mins

The last dose of T3 should be 12 hrs before a blood draw/test.....

(in that case the blood draw should be 5pm.)

If the blood draw was sooner than the 12 hr gap the lab result would show an elevated FT3 because the hormone had not had time to settle in the system/ serum.

In other words your FT3 would show a " false high" result.

It appears that this is why this endo wants to reduce your T3.

I don't think the issue here is at what intervals you took the T3 but at what time the test was taken in relation to the time and size of the dose.

Only when the correct protocol/ timing is followed for testing can we achieve a reliable result.

I'm assuming that is what you were trying to point out to the endo when you explained...

I took my T3 10mg at 5am(I normally take it at 8am but we're travelling to Liverpool so took 10mg at 5am)

You knew the FT3 result would be abnormally high because...

a) you had taken a double dose

b) the test was too soon after that dose

But the endo didn't appear to take this on board.

Instead, she drew her conclusion on the basis of the abnormally high FT3....and tried to reduce your dose on a wrong premise

As I see it the only way to resolve this, before your dose is changed, is to insist on another blood test taken 12 hours after the last T3 dose because right now you have unwittingly given this endo enough reason to reduce your T3.

This is not your fault birkie but circumstances have conspired against you and you need to take a stance ...if you have been doing well on your current dose.

TiggerMe profile image
TiggerMe in reply to DippyDame

When my Endo requests bloods it stipulates 3-4 hours after last dose.... obviously I ignore this and leave 24 & 12 hours respectively for T4 &T3... so even with a 6 hour gap it might be a tough argument to have with an Endo if this is the way they like to test?

I'm surprised after a relatively small dose there is still that much swilling around in the blood rather than getting to the cells after 6 hours?

With normal dosing pattern being 8am, 1pm and 6.30pm

This bit confuses me... is the test accurate do you think? Any biotin supplements?

But your right in what you said about me having my last does of 5mg at 6.30pm...maby if I'd taken it later the result would have been higher.. It was 5.4 (T3 level) TSH 1.77 taken last 5mg at 6.30pm.

birkie profile image
birkie in reply to DippyDame

Well unfortunately I'm not doing OK on my dose, I struggle to increase to 25mg split ,which gave me a reading of T3 5.4 and TSH of 0.05...I'm having gut issue with my meds even had the same on T4 that's why another endo put me on T3 only not this one.But this endo I saw was not for thyroid but for parathyroid, 3 glands appear to have gone over active.

But she popped a thyroid test in, and as I said I'd taken my T3 (10mg) at 5am...she seemed to think that 10mg at 5am and blood taken at 11.15, I should not have had such a high T3 of (11.4) 🤷‍♀️ then I would have taken the next dose of 10mg at 1 o'clock which she said would push the t3 higher, she thinks I could be hypersensitive to it, keeping my over medicated.

Be interested to see what she says in 2 weeks time.

But she's not taking me off it, I'm only with her for parathyroid, but she is interested in my thyroid levels 👍

Beau55 profile image
Beau55

Hi Birkie, are you t3 only or taking 25 on top of Levo? Sorry I couldn’t find it anywhere so assuming you are t3 only.

I would say to disregard the test completely. Testing whilst on t3 monotherapy is rather redundant in the first place and you are better dosing via signs and symptoms including HR, BP, temp etc. My two endos have confirmed this but they are not nhs. I can understand though that if you are limited by an nhs Endo then you have to work to their principles which will include testing. So I would argue that you took your dose too close to the test which is showing a falsely elevated t3 and you want retesting when you haven’t taken a dose. I would never test within 12 hours of a dose for this reason if I was depending on an nhs Endo to dictate my treatment this way.

Paul Robinson has a great page on why t3 testing on t3 only is a bad idea paulrobinsonthyroid.com/can...

birkie profile image
birkie in reply to Beau55

Thank you for the reply, this endo is pretty good it's only taken me 3 years to get a diagnosis of primary hyperparathyroidism because the 3 endocrinologist I have seen( nhs🙄,said.. first I do have it, then "ho we don't think you have it" 🙄 then said we'll watch and wait.I was not prepared to do that as I'd been diagnosed the first time in 2004,... then again by those 3 endocrinologists in 2020.

I took it into my own hands and saw a parathyroid surgeon who found one overactive parathyroid gland, he sent the report to my gp and eventually I got to see this endo in Liverpool.

I can't fault her.. She saw my bloods, did the pet scan, showing 3 anomalies, and as confirmed I do have primary hyperparathyroidism.. So thank god for her💓

But she did a thyroid test same day.. Given I'd only taken 10mg at 5am had bloods taken at 11.15..the endo thought it was strange the t3 was still high at 11.4..she said even after 6 hours she wouldn't expect to see that level.

She did say gut issues absorbancy can contribute to slow uptake causing T3 to pool, then you take your next 10mg before your T3 level comes down maby causing you to be hyper.

As I said she's looking into it and getting bk to me, she isn't taking me off it, she's just concerned, especially when my parathyroid hormone is playing up to👍

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