Blood test protocol and aim for T3 and T4 - Thyroid UK

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Blood test protocol and aim for T3 and T4

ak_83 profile image
9 Replies

I am a male with hypothyroidism (Hashimoto's) for a few years now. I've arrived at the conclusion that I need a mix of synthetic T3 and T4. The trick is to get the right amount of each... I have been following the advice of taking the blood test first thing in the morning before breakfast and hormones. The previous intake of T4 is previous morning (24 hours) and previous intake of T3 is evening (~12 hours).

I have also tried to aim of having ~60% of range for both T4 and T3 for my blood test results. Someone here suggested that a lot of people feel good on those sorts of numbers. I know everyone is different, but I needed some kind of anchor to go for as my symptoms are quite confusing to judge.

My question is, is the above the latest understanding of the protocol and the test targets?

My issue with taking T3 in the afternoon on the day before the test is that it is difficult to simulate the morning conditions - the exact time and more importantly how it metabolises given I've eaten (different things for lunch before taking it so it digests differently) through the day. Also, by taking T3 in the afternoon, I don't take the morning dose, so my T3 is decreased by an extra 12 hours. Normally I take my T3/T4 early morning with a glass of water 60-90 minutes before breakfast. I've found that my blood tests fluctuate, possibly because of these variables. I wonder if there is a different formula where I can take T3 as usual in the morning with my T4, so have 24 hour delay instead of 12, but then I just adjust my target to maybe 40% of the range or similar? This way the blood test conditions would be much more consistent - I just need to get a realistic target.

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radd profile image
radd

ak_83

The delay is aimed to capture the highest TSH & an average thyroid hormone level by avoiding the peaks & troughs that are a natural consequence of medicating T3 given its short half life. This offers best possible chance of gaining enough meds via prescription as many GP’s dose via TSH, and if tested prefer T4/T3 numbers lower in range.

Remember this percentage-through-range suggestion is only that - a suggestion. I function best with lower levels and others might need top of range. Our hormone levels fluctuate according to many factors and tests taken at different intervals can offer other but just as relevant information. For example for a while I tested 2 hours after taking meds as my private endo wanted to ensure FT3 levels weren’t peaking too high after I had previously suffered psychosis.

For a newbie test results can give a goal & offer reassurance of adequate medication when symptoms lag and there is confusion regarding problems. For a person who has medicated a number of years on a stabilised dose, symptoms become their guide. For instance I am one of the few who increases meds during winter, so when I start feeling cold & lethargic I increase dose by .25mcg grain NDT (equivalent to approx 25mcg Levo) but I don’t test after this change because it is a regime I have practiced for several years confidently knowing I won’t go over range in my numbers. Come the warm spring & I reduce again knowing I won’t become under medicated.

My advice is not to fret about the numbers in regard to achieving wellbeing because you can have great numbers but still feel hypothyroid if the fundamentals of making meds effective aren’t met, ie sufficient iron & nutrients, good gut absorption, low bodily inflammation, balanced blood glucose levels, etc. In this scenario the numbers can cause confusion. The 'sweetspot' has a narrow margin & if being met but there is still room for a dose increase, the inclination might be to just add more meds instead of addressing the other insufficiencies, meaning meds are not going to just remain ineffective but can actually start working against us.

The numbers are important but only in a certain context of preventing over/under dosing, and gaining a prescription in which case it is better to follow the suggested protocol re testing.

ak_83 profile image
ak_83 in reply to radd

Thanks radd, appreciate the view, but the approach failed for me so far. I've tried that before for years just going by the symptoms. I could never find a good spot it was always too low or too high. Hence just trying to ground myself with better suggestions around the testing at this stage. I don't have an issue getting maximum medicine out of my GP. I just want to trust the consistency of my FT3 results and the target.

radd profile image
radd in reply to ak_83

ak_83,

You can only trust "dosing by symptoms' when you have achieved enough well-being from hitting your 'sweet spot' for some time (otherwise other conditions could be masking).

And you can only find your true 'sweet spot' after addressing any insufficiencies that risk inhibiting meds from working effectively (otherwise meds doses risk needing alterations due to improved efficacy as other systems start working more effectively).

You may mind this article posted today helpful.

.

healthunlocked.com/thyroidu...

ak_83 profile image
ak_83 in reply to radd

I guess that's it. I don't know what my sweet spot is, because you need to be at that dose for some months. So I'm trying to find something close to it with the help of blood tests. I still use symptoms, but the tests keep me sane. After I find a dose that's close enough to the target and the symptoms aren't too bad, then I can hold it for longer and see what happens.

radd profile image
radd in reply to ak_83

ak_83,

If meds supply is guaranteed then you can use which ever test timing parameters you want to experiment with, as long as future tests follow suit in order to gain true comparisons.

Keeping a record of our test results & noting symptoms can be especially helpful because with the extensive list of hypo symptoms it is easy to forget/mix up felt progression, regression or indifference.

Also, ensuring iron & nutrients are optimal is one of the basics that helps get meds working effectively. Good luck & I hope you feel better soon.

ak_83 profile image
ak_83 in reply to radd

Thanks radd. Appreciate your comments.

I've had a look at the related posts and found one suggestion: FT3 (~12 hr) = FT3(24 hr) + 20% i.e. I can take my single dose of both T4 and T3 as usual in the morning and take the test 24 hours later. To get comparable numbers of FT3 (e.g. to get to that ~60% through the range target), I would just add 20%. I think this way my tests will be much more consistent as it would remove the dependency of the contents of my digestive system.

Once I get to something close to ideal FT3/FT4, I am planning to redo my iron panel, vit-B12, folate and vit-D. I understand from the posts on this forum that those are the recommendations here for optimal cellular absorption. Aside from the iron panel, my understanding is most vits should be in the upper range? Am I missing anything?

I've had these done before and they were all good except B-12 was not in the upper 75% of range, so I supplemented and got it high in the range. That was 2-3 years ago. I've also supplemented with a LOT of stuff over the years and got a bit disenchanted by nothing helping and spending thousands or even tens of thousands of dollars on them.

Additionally, I've read that magnesium (not sure which form is best for Hashi) is another cellular energy puzzle piece. So might do a round of supplementation of that too. Again, first I want to get the T4/T3 as sorted as I can and then go back to the vit tests and supplements. Is there anything else in popular understanding on this forum that helps with cellular energy/T3 cell utilisation?

radd profile image
radd in reply to ak_83

ak_83,

Oh good, you have found it.

I was trying to find you that. It was a formula one of our old admins Clutter used to use. I am not wholly sure how accurate it is but if this is your new testing protocol, so long as it is consistent, true comparisons will be available.

I agree having to move meds timings about should be avoided if possible. Life can be confusing enough as it is. I took my meds twice yesterday for the first time ever! Nothing happened (thank goodness) except I felt a little hot 😬.

If gut absorption is good, you should receive the micro-nutrients from foods but many members have to supplement a bit of zinc, selenium, etc, as all good for thyroid hormone conversion. I have just started magnesium for restless legs at night time.

This interesting link was supplied to me by another member.

drjockers.com/best-magnesiu...

ak_83 profile image
ak_83 in reply to radd

Thanks radd. Am reading your magnesium article...

shaws profile image
shawsAdministrator

I take T3 in one daily dose when I get up with one glass of water, I wait an hour before I eat. I have a life and am symptom-free.

This was as advised by an expert (doctor/scientist/researcher) on the use of T3 .

Dr John Lowe (scientist) took his one daily dose of T3 the middle of the night so that nothing interfered with its uptake. He was also an Adviser to Thyroiduk.org/uk before his death, due to an accident. He also stated that T3 has to saturate all of our T3 receptor cells and it then sends out 'waves' throughout the day..

This method suits me.

When having a blood test I do not take T3 until afterwards. I get the earliest appointment (made weeks ahead) and only drink water before blood draw.

There's never a query about my results. (except that one doctor told me that T3 converts to T4!

healthunlocked.com/thyroidu...

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