T4 test too high! : May I ask for some thoughts... - Thyroid UK

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T4 test too high!

pixiewixie profile image
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May I ask for some thoughts & advice please. My latest thyroid Function blood results show TSH 0.01 & the T4 level as 30. I don't have the T3 results. My surgery's pharmacist wants me to cut down on Levothyroxine immediately. He said there are serious health risks from being over medicated on Levothyroxine which is shown by these results. Currently I am on Levothyroxine 150mcgs daily & do not feel as if I need to decrease the medication. I have had Hashimoto disease for over 20 years & it took a while to get stable & I don't want to end up as poorly as before. I do have various other autoimmune issues. Do you know why T4 should be elevated? Do I need to cut back on Levothyroxine ? Thank you so much for your thoughts. Best Wishes to all.

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SlowDragon profile image
SlowDragonAdministrator

was test done early morning, ideally around 9am and last dose levothyroxine 24 hours before test

Do you always get same brand levothyroxine at each prescription

EXACTLY what vitamin supplements are you currently taking

When were vitamin D, folate, ferritin and B12 last tested

As you have Hashimoto’s are you on strictly gluten free diet and/or dairy free diet

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

List of private testing options and money off codes

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

bluehorizonbloodtests.co.uk...

Just Thyroid includes BOTH TPO and TG antibodies -£49

randoxhealth.com/at-home/Th...

If you can get GP to test vitamins 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/

Monitor My Health also now offer thyroid and vitamin testing, plus cholesterol and HBA1C for £65 

(Doesn’t include thyroid antibodies) 

monitormyhealth.org.uk/full...

10% off code here 

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

NHS easy postal kit vitamin D test £29 via

vitamindtest.org.uk

Only do private testing early Monday or Tuesday morning. 

pixiewixie profile image
pixiewixie in reply to SlowDragon

Thank you Slow Dragon. I do always have the same brand levothyroxine. I have not been taking my vitamin D as regular as I should & it has not been tested for a while. Thank you for all the information for getting tests done ... I much appreciate that information. I didn't realise that Hashimoto would be totally better on gluten free ... I take gluten containing products & very minimal dairy. Is it very important that no gluten nor dairy products be consumed as my diet is very minimal? This test was done randomly at a hospital appointment ( not for thyroid), I had my thyroid medication consumed four hours before and had not been fasting as I usually do. Thank you for your informative reply. Very best wishes.

waveylines profile image
waveylines in reply to pixiewixie

If you took your levothyroxine 4hrs before the test then the test is invalid. This because there needs to be a fast of 24hrs before testing. Its probably why your test came back high. Tell the pharmacist you weren't aware the test was being done & had taken your levothyroxine. Tell him your happy to do a repeat test but it needs to be carried out per correct protocol....ie 24hr fasting. Good luck. 🤞🤞

pixiewixie profile image
pixiewixie in reply to waveylines

Thank you so much waveylines. Usually I do this but it was done at a hospital clinic so not prepared. l asked the pharmacist for a repeat test ...they said in 6 plus weeks. I will get a private one if there is any problems especially if they can't measure T3 too. Thank you so much for your reply.

waveylines profile image
waveylines in reply to pixiewixie

No problems Pixiewixie. So they should leave you alone for another 6 weeks. Personally I wouldn't change the dose unless a valid test is done. Hospital have done this to me too! All my sympathy.

pixiewixie profile image
pixiewixie in reply to waveylines

Thank you for your thoughts waveylines ... much appreciated.

SeasideSusie profile image
SeasideSusieRemembering

pixiewixie

What is the reference range for your FT4 test?

When did you take your last dose of Levo before the test (last dose should be 24 hours before to avoid a false high or false low result).

As you have Hashimoto's you could possibly be going through a "false hyper" phase and might need a temporary reduction in your Levo.

It's also possible that you may not be converting T4 to T3 very well and need a high FT4 to give you a decent level of FT3. So you definitely need to have FT3 tested at the same time as TSH and FT4, if your GP can't get this done then it's a good idea to do a private test with one of our recommended labs.

What are your current nutrient levels like? Are they optimal? We need optimal levels of Vit D, B12, Folate and Ferritin for thyroid hormone to work properly and good conversion to take place, so if not done recently these tests are also important.

pixiewixie profile image
pixiewixie in reply to SeasideSusie

Thank you SeasideSusie. The reference range for the FT4 test was 12.0 -22.0 pool/l. As the test was done at a hospital clinic ( not relating to thyroid), I was not prepared. Thank you for all your information which is both enlightening and helpful. I will get the test redone ensuring T3 is also done. Thank you for all your helpful information regarding the supplements also. I had not considered a "false hyper" but will take that onboard too. How long can they last ? Thank you so very much.

SlowDragon profile image
SlowDragonAdministrator in reply to pixiewixie

you ideally need to test vitamin D twice year

Once in summer once in winter

Test folate, B12 and ferritin at least annually

Important to maintain GOOD vitamin levels

High Ft4 is false result as you took levothyroxine (Ft4) before test

pixiewixie profile image
pixiewixie in reply to SlowDragon

Thank you SlowDragon for all this information ... it is of great help.

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