Thyroid loading test : Has anyone has this done... - Thyroid UK

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Thyroid loading test

DawnieA profile image
33 Replies

Has anyone has this done? My bloods have been up the swanny so they are checking to see how/if I’m absorbing thyroxine.

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DawnieA
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33 Replies
SeasideSusie profile image
SeasideSusieRemembering

Can you explain what a thyroid loading test is, I've not heard of that?

helvella profile image
helvellaAdministratorThyroid UK in reply to SeasideSusie

SeasideSusie,

Sounds like they check FT4, give a tablet, check FT4 again.

So many questions about exactly what they will do, and what they should do.

If test results are so variable, it rather suggests variable absorption. Which makes me wonder how to take the results of a single, one-off, absorption test?

SeasideSusie profile image
SeasideSusieRemembering in reply to helvella

Thanks Rod :)

DawnieA profile image
DawnieA in reply to SeasideSusie

Apologies I should have explained a bit more. I had one done yesterday. They take baseline reading when you arrive. Give you a huge dose of thyroxine, 1000mg (1g) and then measure bloods every hour for 4/5 hours. You don’t take your normal thyroxine daily. They do this each week on the same day and at the same time for 3/4 weeks depending on results. Just wondered how people felt afterwards and what the outcomes were.

SeasideSusie profile image
SeasideSusieRemembering in reply to DawnieA

Thanks Dawnie.

Would you mind doing a follow up post when you know the outcome of the tests. I'm intrigued and it would be interesting to know what conclusions the doctor comes to and how you feel about it.

DawnieA profile image
DawnieA in reply to SeasideSusie

Of course I will, Ive baffled the docs. They’ve even sent bloods from my test yesterday to 2 other hospitals to compare results.

helvella profile image
helvellaAdministratorThyroid UK in reply to DawnieA

DawnieA,

Did you see diogenes' response on your other question? He is a very real expert in thyroid testing.

(By the way, to save everyone from heart attacks, I *think* you meant 1000 micrograms (1 milligram)! :-) Which is still a large dose.)

DawnieA profile image
DawnieA in reply to helvella

Ha ha, yeah you’re right on the dosage, knew it was high and 10 pills to take in one go 🙈. Will re-read previous posts again. My heads been cabbaged with it all tbh. X

Greybeard profile image
Greybeard

Have you had your antibodies tested? When they are active they give variable results for tsh, t4 and t3. Some endos seem to think they are irrelevant.

DawnieA profile image
DawnieA in reply to Greybeard

Yeah, no antibodies. I do have Hash’s tho. Had right hand side out 5 years ago which showed hashs. Current bloods are TSH over 150 (off the scale at hospital), T4 30, T3 -2. Been UA for 23 years, never stable, but these are worst bloods I’ve had. See my other post for more details x

Greybeard profile image
Greybeard in reply to DawnieA

If you have hashimoto's there will be antibodies, you may not have been told about them.

DawnieA profile image
DawnieA in reply to Greybeard

It’s very rare to not have antibodies, less than 5% of those wth hashs have no antibodies. Apparently I’m a very unusual case lol x

Clutter profile image
Clutter in reply to Greybeard

Greybeard63,

Some people are sero negative and Hashi's is diagnosed by the damage seen on ultrasound scans.

Clutter profile image
Clutter in reply to DawnieA

DawnieA,

Some other things for consideration when both TSH and FT4 are high if interference to TSH and FT4 assays has been conclusively ruled out:

Resistance to Thyroid Hormone (RTH) and TSHoma a hormone secreting benign adenoma.

DawnieA profile image
DawnieA in reply to Clutter

Clutter, thanks for this. Ive had to push for this test (been asking for years) but have asked for RTH to be considered too. I have another 3/4 loading tests to do yet, so I guess I won’t have answers until then.

humanbean profile image
humanbean

I suspect that the doctors don't believe that you were taking your levothyroxine regularly. They accuse patients of being "non-compliant" quite regularly, whenever the results they get on testing aren't to their liking.

What they are doing is attempting to prove, to themselves and you, that you will absorb Levothyroxine if you take it regularly.

This subject comes up fairly often. A previous post on the subject can be found here :

healthunlocked.com/thyroidu...

Note that "euthyroid" means "normal thyroid".

Nothing would induce me to take Levothyroxine once a week, I would only ever agree to daily dosing. I don't believe it can possibly be good for the heart, and the body generally.

Clutter profile image
Clutter in reply to humanbean

HB,

I don't believe this is a 'compliance' test. They wouldn't be monitoring levels hourly for 4-5 hours unless they were checking absorption.

humanbean profile image
humanbean in reply to Clutter

That may be true. I know I have a tendency to jump to conclusions about the motivations of doctors at the best of times. I wouldn't trust them as far as I could throw them.

It would be interesting to find out the ultimate outcome i.e. what was found, what explanation the doctors came up with, and what they wanted to do about it.

Clutter profile image
Clutter in reply to humanbean

HB,

Hoping DawnieA will keep us updated. Not often we see such results although ThyroidObsessed has high TSH and high FT4, just not to the degree DawnieA has.

humanbean profile image
humanbean in reply to Clutter

I hadn't read the OP's previous post. *Sigh* Brain not working well today. :(

DawnieA profile image
DawnieA in reply to Clutter

I will do x

DawnieA profile image
DawnieA in reply to Clutter

Hi There, just a quick update, I’ve now had 3 thyroid loadings done, my TSH is down to 37 but my T4 is going up and is now at 40. T3 was at 2 before the tests and is now 3.5 (3.5 - 6.5). So I have been asked to go back for another loading this week. The interesting thing is tha one of the results which got sent to another hospital show totally different results for my T4. The 3rd hospital where the blood was sent hasn’t sent results yet.

Clutter profile image
Clutter in reply to DawnieA

DawnieA,

Thanks for letting us know. Good that TSH is lower and FT3 higher but not good that FT4 is higher.

Interesting that T4 result is coming back different. It does suggest something is interfering with assay.

Have you been feeling very hypothyroid or hyperthyroid?

DawnieA profile image
DawnieA in reply to Clutter

Hi, felling massively hypo, my neck is so swollen this week so will be getting them to check it when I go. Constant headache too. Sleeping 10 hours plus but not refreshed, but I do have ME as well. I managed to get all my results since I’ve been to specialist and oddly my T 4 is always high, so I do think there is something with the assay. Hopefully the 3rd hospital will agree with one of the other results so we know where we are. X

DawnieA profile image
DawnieA in reply to Clutter

So after 4 weeks of thyroid loading my TSH is 2.87, T4 has gone up to 49 and T3 is 3. I have an appointment on 13/3/18 to discuss next steps, Doc mentioned that I may not be converting T4 to T3 and so may try me on T3 as well. Watch this space lol x

Clutter profile image
Clutter in reply to DawnieA

DawnieA,

There's no maybe about it. With T4 49 and T3 3 you are not converting T4 to T3!

Did the results combe back from the 3rd hospital?

DawnieA profile image
DawnieA in reply to Clutter

Hi, no the results haven’t come back yet, so I will have a list of questions when I go back in March. As for not converting, that’s what I think too. I thought it years ago and asked for T3 but was refused. May ask for the Di102 test as well x

Clutter profile image
Clutter in reply to DawnieA

DawnieA,

It is DIO2 test not Di102. I don't think DIO2 is available on NHS. You don't need it to determine poor conversion anyway. Low TSH, high FT4 and low FT3 indicates poor conversion.

DawnieA profile image
DawnieA in reply to Clutter

Lol, yeah that’s the test. I mentioned it to my consultant a few weeks back prior to having the loading tests, he didn’t rule it out but said it would be done at Cambridge hospital.

DawnieA profile image
DawnieA in reply to humanbean

I will keep you informed x

DawnieA profile image
DawnieA in reply to humanbean

Hi,

If I had a pound for every Doctor, GP, consultant who asked when I take it, how I take it, how often I take, Id be very rich. I’m fed up of been asked now. After 23 years you’d think I know, but if you’ve seen my other thread you will see how much my results have changed ina matter of days. So this proved a point really, in that even if I missed a dose one day, it wouldn’t change so much. So they’re finally doing something. Blood from the loading test has gone to 3 labs as well. Fingers crossed I get somewhere

humanbean profile image
humanbean

DawnieA

If this problem you're having with your results is a fairly new one, I wonder if you have started taking any new supplements that contain biotin in the last few months? B Complex supplements often contain biotin and so do supplements intended to improve the health of nails and hair. There may be others which contain it too e.g. multi-vitamins.

The reason for asking about biotin is mentioned here, and it is well worth knowing about :

healthunlocked.com/thyroidu......

Anyone taking one or more supplements containing biotin should stop taking them 5 days or so before testing anything.

DawnieA profile image
DawnieA in reply to humanbean

Hi, I just take Vit D and Folate which are both prescribed x

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