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Thyroid UK
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Test results

This is my first post, I was diagnosed hypothyroid in 2010 but had experienced symptoms when I was a small child. Could someone please advise if I need an increase in dose due to symptoms? I take 50mcg levothyroxine, my dose has been as high as 200mcg.

Thank you

Serum TSH - 1.91 (0.2 - 4.2)

Serum Free T4 - 14.3 (12 - 22)

Serum Free T3 - 4.2 (3.1 - 6.8)

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The answer is 'Yes' you do need a rise. Both FT4 and FT3 too low. TSH too high. This is an excerpt from an Ex President of the British Thyroid Association who stated:-

6 What is the correct dose of thyroxine and is there any rationale for adding in tri-iodothyronine?

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

If you'd like a copy to show your GP email louise.warvill@thyroiduk.org.uk

When having tests for thyroid hormones it should be the very earliest possible, fasting (you can drink water) also allow a gap of 24 hours between your last dose of levothyroxine and the test and take afterwards.


Thank you, I fast and I try to get the blood test booked in the morning between 8 - 9. Often the GP secretary looks at me funny when I ask for the earliest blood draws and that I need to fast for them. They tell me I am not diabetic and so not eligible for fasting blood draws. So I just ask for the earliest ones when they are available. I leave a whole 24 hours between the dose and the test and I take the medication afterwards.

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We have a choice for the timing and it's one that suits us not the secretary. It's nothing to do with her and you don't need to give explanations and they do not understand why it's important for us to get the best out of our blood test. It is imperative and may be the difference between feeling well or unwell. Just to check - you allow 24 hours gap between last dose of levo and the blood test and take it afterwards.

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The secretary is an administrator.

If you feel you need to give an excuse why you must have an early appointment simply say I need to be leave for work/back to care for someone so x can go to work/whatever by 9.15am.

Both my terrible ex-GP and current GP's practices offer appointments twice a week in clinics that start by 7.30am because they realise that some people cannot go to the GP during the working day. So those in the NHS are aware they deal with lots of social issues so making it hard for people to attend appointments results in them ends up increasing their own work load.


I see. Thanks for this. :)


If they have not been done ......Suggest you ask GP to check levels of vitamin d, b12, folate and ferratin. These all need to at good (not just average) levels for thyroid hormones (our own or replacement ones) to work in our cells

Also have you had thyroid antibodies checked? There are two sorts TPO Ab and TG Ab. (Thyroid peroxidase and thyroglobulin) Both need checking, if either, or both are high this means autoimmune thyroid - called Hashimoto's the most common cause in UK of being hypo.

TPO is rarely checked and TG almost never checked. More common to have high TPO or high TPO and high TG, but negative TPO and raised TG is possible, though much rarer. There are a few members on here that have this, often they have struggled to get diagnosed.

ALWAYS Make sure you get the actual figures from tests (including ranges - figures in brackets). You are entitled to copies of your own results.

If you have Hashimoto's then you may find adopting 100% gluten free diet can really help reduce symptoms, and lower TPO antibodies slowly over time too.

Selenium supplements can help improve conversion of T4 to T3 and may also lower antibodies


Thanks I know thyroid antibodies, ferritin, folate, vitamin D and B12 have been done. A few others have been checked as well. I am going to the doctor soon to get copies of them.

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