helvela Re don’t stop thyroxine b4 blood tests - Thyroid UK

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helvela Re don’t stop thyroxine b4 blood tests

Ashupan profile image
15 Replies

Taking the thyroxine on the morning of the test, would only confuse the inexperienced. It will change your T4 levels slightly, and not influence your TSH. It won't impact my interpretation of your results. It is not worth worrying about. The vast majority of doctors are experienced enough to understand the influence of Thyroxine on blood results that the changes to results are largely irrelevant.

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Ashupan profile image
Ashupan
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15 Replies
Hedgeree profile image
Hedgeree

Hi Ashupan,

Your post reads like a reply to another post? Was that your intention?

RedApple profile image
RedAppleAdministrator in reply to Hedgeree

I think it's a response to the reply by helvella in this post healthunlocked.com/thyroidu...

SlowDragon profile image
SlowDragonAdministrator

The vast majority of doctors are experienced enough to understand the influence of Thyroxine on blood results that the changes to results are largely irrelevant.

And this is frequently not true

Medics should ask patient how long before last dose levothyroxine was taken before test

If someone takes their Levo before test and Ft4 results is falsely high, they often then get Levo dose reduced inappropriately

RedApple profile image
RedAppleAdministrator

Ashupan, Your profile says you're in Australia. Is this correct? If so, perhaps you are fortunate enough to have a doctor who actually does understand how to interpret thyroid hormone test levels. Most do not.

arTistapple profile image
arTistapple

I admire your confidence in doctors and their knowledge. In the U.K. we have no such confidence. Our doctors do not understand anything but the absolute basic about hypothyroidism. “You take this pill for the rest of your life. In a few weeks you won’t know yourself” presumably with their fingers crossed out of sight under the table.

Ashupan profile image
Ashupan in reply to arTistapple

The GP in Aus is not the person we deal with for blood results. It’s the endocrinologist. He’s the dude who decides the amount of thyroxine I need etc.

My GP gets a copy of results too. And yes I trust him too.

I am sorry so many people in UK , what I read, have so many worries and can’t get the tests or meds they need.

Makes me feel awful.

Here, it’s opposite.

Today been given date for PET scan very early morning of Aug 5 th, then straight into Admission for RAI treatment.

Am terrified of saliva gland issues.

But back to thyroxine and blood tests.

I just know that the GP and experts All take into account the results based on if one takes meds before bloods drawn.

They really are clued up. Thyroid probs enormous here.

Said with respect

helvella profile image
helvellaAdministratorThyroid UK

TSH can change enough to affect interpretation.

Ashupan profile image
Ashupan in reply to helvella

Exactly. Which is why the results are therefore read accordingly

helvella profile image
helvellaAdministratorThyroid UK in reply to Ashupan

But how does a GP achieve that?

They do not have the knowledge or experience to do so. And changes in TSH can be extremely individual.

Plus, as I said earlier, I doubt you'll find a single member who has been asked when blood draw was done. Sometimes that will be on the results, but not always.

Ashupan profile image
Ashupan in reply to helvella

I don’t want to argue. Guess it’s up to advising the clinic where u give blood, let them know u took thyroxine or not. Clinipath the blood place, asked me. She then noted for doc I had/ hadn’t taken meds prior to bloods.

Secondly, I think UK and Aus docs all hv similar training. My doc has made a point of telling me he has done more research since I got thyroid cancer. It was thru his tests gor me, that we found out diagnosis.

I see a doc in England when I am there. This doc also listens to me and is very proactive in all that’s done.

Lastly yes changes are individuall. But surely each individual is dealing with his or her doctor, who sees her/ him as an individual. And reads their blood diagnoses each time and gets an individual idea of what’s going on.

I can’t believe uk docs are not caring for each person on a one by one basis.

That’s surely what doctors do?

If I didn’t hv faith, I would change surgeries

helvella profile image
helvellaAdministratorThyroid UK in reply to Ashupan

I can absolutely state that some doctors insist that time of taking dose is utterly irrelevant and will not affect any blood tests at all. We see that day after day here (though not always stated quite to clearly).

Such doctors obviously will not be making any adjustments at all - because they do not believe any need to be made.

I have personal experience of seeing a doctor who had little idea and would have been totally flummoxed had this issue even come up.

I'm glad yours are looking after you.

Ellie-Louise profile image
Ellie-Louise in reply to Ashupan

If only that were true.

My surgery is made up of partners, it is a teaching surgery so there are also locums in attendance.

We are very lucky if we see the same doctor at an appointment, my last 3 tests were all seen by a different doctor each time and every one had a different opinion to another.

Last week I had to INSIST on speaking to my own registered doctor in order to sort out my dosage, thankfully he at least, understands that I take advice from this website and lets me decide for myself what to do.

But I hadn’t managed to get to him once in over the last 2 years until now. He’s the one I trust most of all, out of all of them.

Hi Ashupan, I’m so sorry that you’ve got the challenges and worries from your cancer treatment, but I see some amazing responses to all your earlier posts with shared experiences.

Out of curiosity, what dose of Levo are you on right now and what were your latest blood test results for TSH, Free T4 and Free T3?

Ashupan profile image
Ashupan in reply to FallingInReverse

12cmg Eltroxin( I get 200 tablets in a packet).

TSH 0.27low ( on thyroxine therapy, TSH is reduced.)

Free T4. 14

Free T3 4.4

Then the second lab

TSH 0.27

Free T4 14

Thyroglobulin Ab 187.8 high

FallingInReverse profile image
FallingInReverse in reply to Ashupan

Do you have the ranges for those results?

What dates were these and how long had you been on the (I’m guessing that should be) 125 daily? And per the above discussion - how long before the blood draw had you taken the Eltroxin?

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