Recent TSH check

[Blanco1]

My husband started on Levothyroxine 2010 has had annual check ups medication slowly increasing - now at 150mcg. Following a recent blood test his TSH has gone from 6.72 down to 0.07! Any thoughts???

[SeasideSusie Remembering]

Blanco1

We might be able to help if we have more information

When was his TSH 6.72? What dose of Levo was he on at the time?

Is the new TSH of 0.07 the result of the next test after the result of 6.72, or has his TSH gone down in increments over time?

How does he feel?

What has his GP said about the new TSH of 0.07? Is he changing his dose of Levo?

TSH on it's own is not enough. It's not a thyroid hormone, it's a pituitary hormone which tells the thyroid gland to produce thyroxine if it detects there's not enough. The thyroid hormones are FT4 and FT3 and these need to be tested too to know if we are optimally medicated.

The aim of a treated hypo patient generally is for TSH to be 1 or below or wherever it needs to be for FT4 and FT3 to be in the upper part of their respective reference ranges when on Levo if that is where you feel well.

If you can give the reference ranges with any results you post we can interpret them, ranges vary from lab to lab so we need the ranges from the lab that did the test.

Has he had thyroid antibodies tested?

[Blanco1 in reply to SeasideSusie]

Of course so sorry I'll give you as much as I have. November 2016 result T4 14.3, TSH 6.72 - was taking 125mcg Levothyroxine, advised to increase to 150mcg Levothyroxine and repeat in 3 months (at the time we didn't know to repeat in 3 months). We left the UK April 2017. My husband returned October 2017 for a blood test result T4 21.1, TSH 0.05 but it states on follow up action - no further action (again we didn't know this until recently). Now living abroad wanted to continue with reviews. Bloods taken this month T3 0.74, T4 10.62, TSH 0.07. (UK blood tests have never included T3 so I couldn't give you that information). My husband has not noticed any ill effects, I note at times over the year being more 'snappy'. Since moving abroad - this has been very stressful for my husband he would say he's always been a worrier. No other tests performed I'm alarmed at the readings and more so for how long it's been low. Any advice grateful many thanks.

[SeasideSusie Remembering in reply to Blanco1]

Do you have the reference ranges for all these tests? They vary from lab to lab so to make sense of the results the ranges are needed.

However, TSH of 6.72 was way too high and an increase in dose of Levo was correct. Retesting should be done 6-8 weeks after any dose change to check new levels.

The October 2017 results must have had FT4 within range, for no change in dose, but most doctors would freak out at such a low TSH. However, TSH is irrelevant when taking thyroid replacement hormone. TSH is not a thyroid hormone, it is a pituitary hormone and it tells the thyroid gland to produce thyroxine when it detecs there isn't enough. When the TSH is low the pituitary knows there is enough thyroxine (either natural or replacement). So FT4 and FT3 are the only important results when on replacement hormone.

Bloods taken this month T3 0.74, T4 10.62, TSH 0.07.

Again, reference ranges needed to make sense of these. Also, that T3 looks like Total T3 and that is not a useful test. Total T3 measures hormone both bound to protein and unbound (free) and it is the free hormone which is taken up by the cells. So Free T3 is the only useful test when testing T3.

So with those new results, we need to know the reference ranges of the T3 and T4, and if they are Total T3 and Total T4 or Free T3 and Free T4.

So don't be alarmed at the low TSH, unless FT3 is over range he's not overmedicated. If FT3 is over range then he needs to lower his dose of Levo.

[Blanco1 in reply to SeasideSusie]

Hi many thanks for such a detailed explanation I hope the following helps: (this was in the UK) Nov 2016 free T4 14.3 (range 11.0 - 26.0), TSH 6.72 (range 0.27-4.2). October 2017 free T4 21.1 (range 11.0 - 26.0), TSH 0.05 (range 0.27 - 4.2). Now the most recent was done in Spain T3 total 0.74 (range 0.45 - 1.65), T4 total 10.62 (range 4.20 - 12.00), TSH 0.07 (range 0.38 - 5.33) and they have "***" this and made reference to see a specialist as the Doctor was unsure but as you say the total T3 & T4 is not a useful so would we need to go back. How low can TSH go? Many thanks.

[SeasideSusie Remembering in reply to Blanco1]

Blanco1

Now the most recent was done in Spain T3 total 0.74 (range 0.45 - 1.65), T4 total 10.62 (range 4.20 - 12.00), TSH 0.07 (range 0.38 - 5.33) and they have "***" this and made reference to see a specialist as the Doctor was unsure

**** This is because The TSH is below range. But the T4 and T3 are within range. They are going by TSH only which is wrong. For some reason the medical profession have not understood that it is the actual hormone levels that are going to tell them what they need to know.

It can be suppressed, and that's offical from the British leading endocrinolgist Dr Anthony Toft who was past president of the British Thyroid Association. He said this in Pulse magazine (the magazine for doctors)

"The appropriate dose of levothyroxine is that which restores euthyroidism and serum TSH to the lower part of the reference range - 0.2-0.5mU/l.

In this case, free thyroxine is likely to be in the upper part of its reference range or even slightly elevated – 18-22pmol/l. Most patients will feel well in that circumstance.

But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l.

This 'exogenous subclinical hyperthyroidism' is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l)."

He recently confirmed, during a public meeting, that this applies to Free T3 as well as Total T3.

You can obtain a copy of the article by emailing Dionne at [e-mail] print it and highlight question 6 to show your doctor.

[Blanco1 in reply to SeasideSusie]

I will get a copy of that which sounds really interesting. Thank you so much for all your help - we have learnt so much tonight. Regards.

[Blanco1 in reply to SeasideSusie]

Hi I have tried to email for a copy and I have double checked the spelling of the email address but it is not being delivered - is there somewhere else I can get that article? Thank you.

[SeasideSusie Remembering in reply to Blanco1]

[e-mail]

Copy and paste, see if it works. It should.

[SlowDragon Administrator]

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also extremely important to test vitamin D, folate, ferritin and B12

Low vitamin levels are extremely common, especially if Thyroid antibodies are raised

All thyroid blood tests should ideally be done as early as possible in morning and fasting. Do not take Levothyroxine dose in the 24 hours prior to test, delay and take immediately after blood draw. This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

Is this how he does his tests?

[Blanco1 in reply to SlowDragon]

Hi no - no one has ever said this the only thing they ask is if has fasted and he has. This all sounds very confusing and worryingly.