Thyroid UK

Stubbornly high TSH

Hello, I'm after a bit of advice. I started taking NDT about three months ago with an immediate improvement in symptoms and energy levels. I started low and worked up to now taking 1.5grain daily. I've always had a very high (>100) TSH, low T4 and regular T3. At my last blood tests my T4 has improved, T3 is high but TSH is 'stuck' at 55.

Yesterday's results: TSH 55, T4 8, T3 7.8

The GP's call me in each time I have a test as my results are always so far out of range but never really have any idea why or how to support me.

I have some symptoms including my ears ringing when I get tired, feeling slightly low energy at the moment and occasionally random pins and needles in feet or fingers. Otherwise I generally feel good. I supplement with flora vital, high dose vit C, zinc, magnesium, selenium and bit E.

Does anyone have any idea why my TSH is so slow to change when my T3 and T4 are improving?

Thanks! Kat

7 Replies

I think the best way to know if medication suits you is how you feel. If well and improving I wouldn't bother too much about the TSH as the blood tests were really brought in when levothyroxine was introduced. NDT contains all the hormones we would usually have.

Before the blood tests were introduced people took NDT until they were well and neither TSH, T4, or T3 could be tested.

If you took too little thyroid hormones or too much, you would soon feel it and either increase or reduce if overstimulated. The first question in this link may be helpful.

1 like

Thank you, I have been feeling so much better taking NDT. It's good to hear reassurance to go with how I feel not just lab results! Thank you for the link too... it's very informative, especially the part in the second question about sleep deprivation. I have two young children had much sleep deprivation until about a year ago. Perhaps my body is still recovering!


Yes, our bodies need time to recover as we may have been developing this illness for quite some time before being diagnosed. Two young children as well, it takes a lot of energy.

Best wishes


There's a possibility it has something to do with the method of lab testing in your area. It may be that there's something in your blood that's interfering with the result of your TSH test. Labs can run different assays (types of test) to get to the answers required and it might be worth your doctor asking the lab for a different assay to be run.

A common-ish problem is the presence of Human Anti-Mouse Antibodies (HAMA) in a thyroid patient's blood - apparently it interferes with one of the standard methods of measuring TSH. Yes, I know it sounds like I just made that up, but I promise I didn't. :) Years ago, labs used to manufacture antibodies using mice as the "vehicle" for development. When injected into humans, some people developed antibodies to the mouse serum - and developed HAMA antibodies.

Ever received any antibodies, blood transfusions? If not, I'm guessing (though I don't really know) that it could be something inherited from a relative. Doesn't do you any harm - just messes up lab test results!

Then again... might have nothing to do with this at all. :)


Thanks lilymay that's really interesting. I've never had any antibodies or blood transfusions but I'll read up on it!


If someone has persistently odd results there are standard approaches to finding out why.

One, mentioned here the other week, is to send samples (ideally taken at the same time - or one sample split as needed) to several labs. If some factor is causing the test result to be inappropriately raised then being tested at several labs, especially if they use different testing technologies, could produce some very interesting results.

A classic cause of elevated TSH results is macro-TSH (macroTSH). This is formed when a TSH molecule gets a TSH-antibody stuck to it. The macro-TSH then shows up an unusually high TSH test result. Some TSH test procedures ensure that they are unaffected by macro-TSH. So getting a sample tested at one lab that is susceptible to macro-TSH and another which is not could clear up the issue.

Another classic cause is some form of TSH-oma - a growth which produces TSH regardless the levels of thyroid hormone. That should also be investigated as a possibility.


PS If some idiot on the internet has an idea what could be done (and double or triple tests are not exactly the most obscure or expensive things to do), why can't your doctors see it?


Thanks Rod, the endocrinologist did send bloods to a different lab in London a while ago but the results weren't significantly different. Thanks for the links though, I'll take the info with me next time I go in and ask them to check for macro-TSH.


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