"Undetectable" TSH on levothyroxine and liothyr... - Thyroid UK

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"Undetectable" TSH on levothyroxine and liothyronine, but I feel fine! Should I be worried about my suppressed TSH if I feel fine?

anglobike profile image
11 Replies

Looking forward to hearing your thoughts!

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anglobike
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SlowDragon profile image
SlowDragonAdministrator

Welcome to the forum

Do you have any other results

For full Thyroid evaluation you need TSH, FT4 and FT3 tested

plus both TPO and TG thyroid antibodies tested at least once to confirm if cause of your hypothyroidism is autoimmune thyroid disease

Very important to test vitamin D, folate, ferritin and B12 at least once year minimum

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water and last dose levothyroxine 24 hours before test

On T3 or NDT - day before test split daily dose into 3 smaller doses, spread through the day at approx 8 hour intervals, taking last 1/3rd of daily dose 8-12 hours before test

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins

List of private testing options

thyroiduk.org/getting-a-dia...

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins by DIY fingerprick test

bluehorizonbloodtests.co.uk...

If you can get GP to test vitamins and antibodies then cheapest option for just TSH, FT4 and FT3

£29 (via NHS private service ) and 10% off down to £26.10 if go on thyroid uk for code

thyroiduk.org/getting-a-dia...

monitormyhealth.org.uk/

NHS easy postal kit vitamin D test £29 via

vitamindtest.org.uk

Link about thyroid blood tests

thyroiduk.org/getting-a-dia...

Link about Hashimoto’s

thyroiduk.org/hypothyroid-b...

SlowDragon profile image
SlowDragonAdministrator

Vast majority of GP’s and endocrinologist are TSH obsessed

As you are on levothyroxine plus T3 it’s virtually inevitable that TSH will be suppressed

No amount of GP reducing dose levothyroxine is likely to change TSH…..but is likely to make you unwell

You will need to see thyroid specialist endocrinologist to “over rule” GP to ensure ongoing access to high enough dose levothyroxine and ongoing prescription for Thybon Henning T3

Roughly where in U.K. are you

Email Thyroid U.K. for list of recommended thyroid specialist endocrinologists who will prescribe T3

tukadmin@thyroiduk.org

Private prescription enables access to Thybon Henning 20mcg tablets at 50p per tablet via specialist U.K. pharmacies

greygoose profile image
greygoose

This thread:

healthunlocked.com/thyroidu...

from earlier today might answer a lot of your questions about TSH. :)

anglobike profile image
anglobike

Update: I remembered yesterday that I read here that taking biotin supplements can cause falsely low TSH readings - which I read somewhere here on the forum, I believe, so I am very grateful to the forum for this information - so I looked it up and found a lot of studies confirming this.

My GP told me that my TSH was "undetectable", not just suppressed, so I am pretty sure that the biotin supplements I had been taking must have affected the testing procedure. When I mentioned biotin supplements as the possible cause, she said she knew nothing about that, so I hope she will be grateful to have learnt about this!

BonsaiKid profile image
BonsaiKid

Mine has been undetecatable for years. The doctor, not an endocrinologist, who prescribed T3 for me told me that it would do that to TSH. However all GPs seem to think that it means you are taking too much T3 and 4.

I have been able to reduce my doses of both over the years but don't feel well on any lower. In fact the last time I tried to reduce my T3 on the advice of the Endocrinologist Consultant they wrote to about it I got very tired in the afternoon and had a 3 week bout of gastric vertigo which I read could be caused by hypothyroid. If you feel fine then I would not worry too much about it.

One thing that I believe enabled me to reduce my doses of both was that I started to take selenium and zinc. Both these are needed for the conversion of T4 to T3 so you might want to find out if you are deficient any either. Best wishes.

anglobike profile image
anglobike in reply to BonsaiKid

Thank you for sharing your experiences with me, I am very grateful to you.

I tried telling the first GP I spoke to about my blood test results that the fact that I was taking liothyronine meant that my TSH would be very low. She didn't believe me and said she would talk about it with an endocrinologist who gave her this information, which she summarised in a text message as follows:

"We have received advice back from endocrinology - they have said that TSH Levels is still the most helpful measure of thyroid hormone replacement irrespective of whether you take T4 only or a combination T3/T4 combination as you are doing.

The TSH levels in your case suggest you are being over-replaced and they would advice (sic) reduction in levothyroxine to 75mcg od. As discussed earlier, in the UK we prescribe levothyroxine dose to 75mcg as discussed previously and rv."

It's so frustrating!

SlowDragon profile image
SlowDragonAdministrator in reply to anglobike

Vast majority of endocrinologists are diabetic specialists and know very little about thyroid especially how taking T3 will almost always suppress TSH

anglobike profile image
anglobike in reply to SlowDragon

I would love to find some scientific paper that mentions this so that I can pass this on to my GP. They are still prescribing me levothyroxine, but they are not happy with my numbers and I am not sure how this is all going to pan out.

In six weeks I am going back for ANOTHER blood draw so that they can test FT3 this time, which the second GP suspects will be "too high".

I wouldn't have even been given thyroid medication here in the UK, I am so glad that my daughter and I were diagnosed in Germany and were given both levothyroxine and liothyronine on request.

SlowDragon profile image
SlowDragonAdministrator in reply to anglobike

Make sure you test as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test

Do you normally split the T3 into 2 or 3 smaller doses through the day

Even if you don’t normally….on day before any thyroid test, split T3 into 3 smaller doses and take at roughly 8 hour intervals with last third approx 8-12 hours before blood test

Essential to regularly retest vitamin D, folate, ferritin and B12 at least annually

anglobike profile image
anglobike in reply to SlowDragon

Thank you very much for your reply, SlowDragon, and please accept my apologies for not replying to you sooner! I saw your message and mentally noted, "get back to it later", but it sadly got forgotten until now.

When I lived in Germany, blood draws were ONLY ever taken fasting, but here I have been given appointments at various times of day and I am not good at fasting so if they call me in at 2pm, then I will have definitely eaten by then 😀

I do indeed split my T3 dose. The Thybon 20mcg tablets can be easily and neatly chopped into four pieces, so I usually take 5mcg with breakfast, lunch and then in the evening at about 4-5pm and around 7-8pm. I don't take any T3 after 8pm. I take my T4 at night, around 2-3am, but I left this dose out before my last blood test. If I recall correctly, I didn't take any T3 on the day before my last blood test, but I am not sure! I think what messed up the results as well may have been the biotin supplements, which I have now discontinued.

As for testing "vitamin D, folate, ferritin and B12 at least annually", are these tests that I can request and my GP will agree to? I was able to do this in Germany and my health insurance paid for them, but will I need to pay for these privately here?

I have been taking vitamin D3 regularly in the last few months so I would actually be curious to see what these numbers look like.

SlowDragon profile image
SlowDragonAdministrator in reply to anglobike

You can ask GP to test vitamins….Some will ….some won’t

Just testing TSH is completely inadequate, and NHS rarely tests Ft3, even for patients prescribed T3 on NHS

Personally I gave up asking and just test privately

Full thyroid and vitamin testing once a year …..either Medichecks or Blue Horizon

just testing TSH, Ft4 and Ft3 via Monitor My Health if need testing between annual test

As you normally take levothyroxine at bedtime/in night ...adjust timings as follows prior to blood test

If testing Monday morning, delay Saturday night dose levothyroxine until Sunday morning. Delay Sunday night dose levothyroxine until after blood test on Monday morning.

Take Monday night dose levothyroxine as per normal

REMEMBER.....very important....stop taking any supplements that contain biotin a week before ALL BLOOD TESTS as biotin can falsely affect test results - eg vitamin B complex

You could consider taking separate folate and separate B12 in week before test

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