Results need further attention, speak to your GP - Thyroid UK

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Results need further attention, speak to your GP

40sgirl profile image
35 Replies

I have been taking Levothyroxine for 35 years, from when I was 42, then I was on 250mg per day, this has over the years decreased to presently 125mg per day. This figure was decided upon in June this year because my TSH and FT results suggested my dosage of 150mg was too high.

Since then I have put on 4lb in weight regardless of reducing food input, I eat very healthy anyway and the edema in my legs has increased significantly. All of which has made me feel really down. added to which I am not sleeping very well. Gardening is my passion which keeps me fairly active.

The upshot of this was I decided to go for a private blood test with a company recommended by yourselves, but I'm struggling to understand what exactly the results mean, can you please advise. I have included the results from June from which my GP decided to reduce my dosage.

June results :- TSH level 0.12mu/L (range 0.27 - 4.2} FT4 32.0 pmol/L (range 9.0 - 26] This test was taken at 11.20 am and I had taken my Levothyroxine at 6.00 am that morning as I had forgotten you need to fast

July results :- TSH level 0.2 mu/L FT4 level 23.7 pmol/L FT3 level 3.9 pmol/L This test was taken at 7.30 am the last Levothyroxine take 25 hours previously.

I would be grateful for any advice with which to discuss this information with my GP

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40sgirl
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Buddy195 profile image
Buddy195Administrator

Hi 40sgirl

Can you supply the range for your FT3 test in July (as laboratories vary). Members can then advise on your conversion rate, which I’m presuming will be low. I’m so glad you repeated the test privately to include FT3 and took your Levothyroxine after the early blood draw.

Have you checked key vitamins (ferritin, folate, B12 and Vit D)? Have you ever had antibodies checked to see if your under active thyroid is auto immune? Have you ever trialled being gluten free?

It appears that your GP is suggesting a reduction in medication as your FT4 was over range in June, due to having taken your full dose of medication too near to the blood draw/ plus (as we all know) many GPS get jittery when TSH falls below 1.

40sgirl profile image
40sgirl in reply to Buddy195

Thank you for your response the range for July was TSH (0.27 - 4.2) result 0.2 mU/L FT4 (12 - 22) result 23.7 pmol/L FT3 (3.1 - 6.8) result 3.9 pmol/LTo the best of my knowledge I have never had an antibody test or key vitamin tests. I am more than willing to go down the route of gluten free is you think it will be of use

pennyannie profile image
pennyannie

Hello 40sgirl and welcome to the forum ;

The accepted conversion ratio when taking T4 - Levothyroxine only is said to be :-

1 / 3.50 - 4.50 - T3/T4 with most people feeling at their best when they come in at a around 4 or under :

So to find your current conversion ratio you simply divide your T3 into your T4 and I'm getting yours coming in at 6.07 showing very wide of centre and your thyroid struggling to utilise the T4 hormone.

Do you have the ranges for the July results please ?

We generally feel ay our best when our T3 and T4 are at around a 1/4 balanced ratio within the ranges and it looks like your T3 is very low in comparison with your T4 but we need the ranges to confirm what looks like an ' obvious ' conversion issue.

T4 is a storage hormone and needs to be converted by your body into T3 the active hormone that runs the body and your ability to convert the T4 into T3 can be compromised by non optimum levels of ferritin, folate, B12 and vitamin D plus inflammation, any physiological stress ( emotional or physical ) dieting, depression and ageing.

Your metabolism appears to have now slowed down too much, hence the weight gain, and when this happens it becomes extremely difficult to extract your core strength key nutrients through your food no matter how well and ' clean ' you eat :

In primary care we are generally managed on just a yearly TSH reading and the odd T4 once in a while, which does tend to result in an ever decreasing dose of thyroid hormone as the TSH after many years becomes some what redundant as a measure of anything.

The TSH was originally introduced as a diagnostic tool to help identify a person suffering with hypothyroidism and it was never intended to be used once the person was on any form of thyroid hormone replacement as then you must dose on T3 and t4 bloods test results.

It is only by testing and monitoring on the T3 and T4 can we see how well you are utilising the thyroid hormone and then we need to find out why you are not converting well the T4 and then offer solutions as to how we can restore your health and well being.

It might be that your T4 dose needs to be reduced a little and T3 - Liothyronine added in to rebalance these two vital hormones but no thyroid hormone works well until all vitamins and minerals are up and maintained at optimal and this is the next step in the process.

Do you take any supplements ?

Are you dealing with any other health issue, or medication that may impact the thyroid hormone absorption.

Do you take the T4 on an empty stomach just with a glass of water and wait an hour before eating or drinking anything. ?

helvella profile image
helvellaAdministratorThyroid UK in reply to pennyannie

Just a note to point out that the ratio depends on the units used. In this case it is clear, but for anyone coming along later.

A ratio calculated from results in moles (pmol/L or similar) will be lower than a ratio calculated from results in (ng/dL or similar).

(T3 is lighter than T4. Even 100% conversion would mean a ratio of 1.2:1 - using mass. But would, of course, be 1:1 - using moles.)

pennyannie profile image
pennyannie in reply to helvella

Thank you - I'll try and remember that for later if talking with a non human being ???

shaws profile image
shawsAdministrator in reply to pennyannie

I did laugh at your comment pennyannie as I have had some comments from a GP that showed he had no knowledge at all of what hypothyroidism patients needed in order to be diagnosed - especially when he stated that T3 converted to T4!!!!!

pennyannie profile image
pennyannie in reply to shaws

Well yes, I was a little confused with the comment actually -

Dr Dolittle & Me self medicating at your service !!!!

helvella profile image
helvellaAdministratorThyroid UK in reply to pennyannie

:-)

A mole is a count of things.

Imagine you have 100 molecules of T4.

You convert all of them to T3.

That means you lose 100 atoms of iodine. (T4 to T3 conversion being deiodination - removal of an iodine atom.)

Your count of molecules is the same - 100. But as they are T3 (rather than T4), they weigh less. There is less mass.

If the T4 molecules are about 100 units of mass, conversion to T3 leaves about 84 units of mass.

The ratio of T4:T3 in terms of number of molecules is 1:1.

The ratio of T4:T3 in terms of mass is 1:0.84 or 1.2:1 (nearly enough).

If you want to go further (I somewhat doubt anyone will :-) ), have a look here:

en.wikipedia.org/wiki/Mole_...

pennyannie profile image
pennyannie in reply to helvella

I trust you and shall take down my Dr. Do Little plaque :

pennyannie profile image
pennyannie in reply to helvella

Looking at these molecules and ratios -

I understand ' in terms of numbers ' :

I accept what you say about ' in terms of mass ' :

Am I going too far down this rabbit / mole hole to suggest that :-

' in terms of ' power ' T3 is around 4 times more powerful than T4 :

Think I'm lost !!!

helvella profile image
helvellaAdministratorThyroid UK in reply to pennyannie

I understand precisely why that is often said. (The exact numbers don't matter - whether we say three times. 3.5 times, four times, etc. We have seen anything up to ten times claimed at times.)

But I think it is the wrong approach - even if it ends up the right number. :-)

Take the 100 molecules of T4 I mentioned earlier.

And assume that T4 has absolutely no impact of its own.

If every molecule gets converted to T3, then we could say it is T3 is exactly equal.

If not one single molecule gets converted to T3, the we could say the T3 is infinitely more powerful.

But reality doesn't allow either of those extremes.

A classic claim is that about one third of T4 gets converted to T3. In my simplistic example 33 molecules of the 100 are converted to T3. That could be said to mean T3 is three times as powerful.

(The other two molecules of T4 get converted to reverse T3 or T4 sulphate or glucuronide, or some other pathway and are excreted.)

In another person, perhaps only a quarter of the T4 gets converted to T3. 25 molecules. That could be said to mean T3 is four times as powerful.

And taking that towards an extreme, consider if only one tenth of the T4 gets converted to T3. 10 molecules. That could be said to mean that T3 is ten times as powerful as T4.

Therefore, the better someone's conversion is, the lower the "more powerful" ratio!

(In order to make this illustration, I've made lots of false assumptions. Such as our conversion capability being a constant ratio. T4 doing nothing. Other substances being inert and having no onward effects. And so on.)

Somewhere in the region of three to four times as powerful seems a reasonable first guess. A useful approximation.

Throughout the above, I have numbers of molecules - moles/molar ratios. For simplicity. (I claim. :-) )

If we are thinking about converting a dose of a medicine, which is always in terms of weight/mass 100 micrograms of T4 could be converted to just 84 micrograms of T3. (Again, assuming perfect absorption and 100% conversion.)

And we need to consider that (typically) only between 60 and 80 micrograms of the 100 micrograms of levothyroxine will be absorbed. Whereas closer to 100% of liothyronine is absorbed.

80% of levothyroxine absorbed and 33% converted would give 26.4 micrograms of T3.

60% of levothyroxine absorbed and 25% converted would give 15 micrograms of T3.

The above is why, while I am happy enough people saying that T3 is three or four times as powerful as T4 in chit-chat, you can't pick a number and work out doses and expect them to work. At best, it might be all we have. At worst, it could be grossly misleading.

Auders profile image
Auders in reply to helvella

Oh my goodness! You have just blown my Sunday afternoon brain!😅 have followed most of it, must admit I do need to keep reading and reading things due to brain fog. You have a way with explaining complicated stuff in a reasonably easy to digest way. Keep up the good work! 😆

arTistapple profile image
arTistapple in reply to pennyannie

I love helvella. However pennyannie you made me laugh out loud. Thank you for cheering me up no end this morning!

40sgirl profile image
40sgirl in reply to pennyannie

Thank you so much for your reply , the ranges are as follows for JulyTSH (0.27 - 4.2 mU/L) result 0.2 mu/L FT4 (12 - 22 pmol/L) result 23.7pmol/L FT3 (3.1 - 6.8pmol/L) result 3.9 pmol/L

I do not take any vitamin supplements as I eat plenty of fresh fruit and vegetables plus meat, poultry and fish. I do take vitamin D during the winter but not in the summer as I spend hours in my garden. Generally I am quite active and I have no underlying health issues. Always take my T4 on an empty stomach but only wait 30 mins before having a coffee.

pennyannie profile image
pennyannie in reply to 40sgirl

Thank you,

We can now see that your July T3 is coming in at around 22% through it's range whilst your T4 is coming in at just over range at around 117% :

Your doctor will likely suggest another dose reduction in T4 unless he knows and accepts these private blood test and the value of T3 as being the active hormone and now too low, and your conversion of T4 compromised.

You maybe lucky and if s/he understands thyroid, run the relevant vitamins and minerals for you, as this is the next step needed :

Reducing your T4 maybe the doctor's suggestion/solution - as it's over range and your TSH too low - but it isn't :

If you meet the NHS brick wall of dogma regarding the TSH being the ' B all and end all ' of thyroid hormone monitoring and dosing - just take a deep breath and run the extra tests yourself.

I found it totally pointless labouring the point with my doctor as it simply exacerbated my symptoms and I now self medicate and am much improved managing my own thyroid health.

Your metabolism - your conversion ratio - has now slowed down too much -

If your only issue is that of weight gain you are very lucky -

If you dip into Thyroid UK who are the charity who support this forum there is a list of hypothyroid - ( low T3 ) and hyperthyroid - ( high T3 ) symptoms on the website and it just might be interesting for you to see how many symptoms you may recognise.

There are now over 126 thousand people registered on the Thyroid UK website - so you are not alone and we are a patient to patient led forum as we all started off on here with just a little question, as to our health.

Remember you doctor may believe that your TSH now shows you as being hyperthyroid and why s/he thinks your dose needs reducing ????

thyroiduk.org

pennyannie profile image
pennyannie in reply to pennyannie

Koola

40sgirl profile image
40sgirl in reply to pennyannie

Hi pennyannieI now have results from the private blood test (Blue Horizon). You asked what vitamin supplements I take. I don't take any supplements, I take vitamin D in the winter but not in the summer.

As you suggested they are saying I'm hyperthyroid but that is not how I feel.

So here are the results I'm still as confused as I was

Biochemistry

CRP 2.11 <5.0 mg/L

Ferritin H 287.0 13 - 150 ug/L

Magnesium 0.93 0.66 - 0.99 mmol/L

Hormones

Cortisol (random) 306 6am - 10am 166-507 nmol/L

4pm - 5pm 73.8 - 291

Thyroid function

TSH L 0.15 0.27 - 4.20 mU/L

T4 Total 114 66 - 181 nmol/L

Free T4 H 22.6 12 - 22 pmol/L

Free T3 3.8 3.1 - 6.8 pmol/L

Immunology

Anti Thyroidperoxidase abs <9.0 <34 IU/ml

Anti Thyroglobulin Abs 18 <115 IU/ml

Vitamin D (25 OH) 50 Adequate 50 < 75

Vitamin B12 323 145 - 569 pmol/L

Serum Folate 9.99 8.83 - 60.8 nmol/L

Apparently my iron levels are showing too high do you think I need further advice with regard to that or is it still a thyroid issue. I would be grateful for your thoughts on this . Thank you

pennyannie profile image
pennyannie in reply to 40sgirl

Hello again ;

Might I suggest that you start a new post with your results so all forum members can help you - writing just to me means I am the only one notified.

New information deserves a new question on the main forum so all forum members can help and advise as I don't pretend to know everything about thyroid, and we all learn from each other.

Forum members will look back at this first post to remind themselves - so there is continuity - so just start a new question with these results and we look back at your previous to remind ourselves :

So from what I can see :-

Your CRP - which is an inflammation marker is under range and we generally have some level of inflammation going on - so without having any comparisons - ok :

Your ferritin is high and this is a question for you doctor : it could be nothing but needs further examination :

Magnesium looks ok :

I don't know about cortisol:

Your thyroid immunity antibodies are ok :

Your TSH is at 0.15 and your T3 at 3.80 and your T4 at 22.60

T4 needs to convert into T3 in the body - and it's apparent this is not happening :

Your T3 is at 19% and your T4 at just over 100% through their ranges :

You are not converting the T4 - Levothyroxine and must be quite unwell :

If nothing else this result is pretty much consistent with your previous results but you do need to be looking at your vitamins and minerals :

I took me over a year to build up my vitamins and minerals and I now eat very clean and cook from scratch and I still supplement on a daily/weekly basis to be optimal and to be able to utilise the thyroid hormone replacement and keep as well as I can be.

Low stomach acid is common symptom when ageing and a known side effect when hypothyroid and if you don't have enough circulating irrespective of what you eat your body may not be able to break down your food to extract your essential key nutrients from your food.

There is a low stomach acid test - the baking soda burping test - you probably have the necessary in the cupboard - just test yourself - and wait and see how long it takes you to burp - I gave up after 10 minutes : details on several internet sites -

I find I need to maintain my ferritin up at around 100 :

with a folate at around 20 :

serum B12 at over 500 ++ ( active B12 75++ ) and vitamin D at around 100 :

Please throw up your blood tests in a new question as you deserve everybody's input and the necessary links to the reasons why

40sgirl profile image
40sgirl in reply to pennyannie

Thank you for your response, I have phoned the Doctor this morning and they will return my call today. I have always cooked from scratch, using vegetables and meat sourced from local quality suppliers but I have now ordered a thyroid supplement booster with added vitamins and minerals.I will let you know if the Doctor is helpful. Kindest regards

pennyannie profile image
pennyannie in reply to 40sgirl

I wouldn't order a thyroid supplement nor a mix of vitamins and minerals :

We need each vitamin and mineral supplemented independently at different times during the day and thyroid supplements are a mixed bag of ' stuff ' and not recommended .

pennyannie profile image
pennyannie in reply to 40sgirl

Looking back at your profile you were previously on Nature Thyroid - a brand of Natural al Desiccated Thyroid - and which will have contained trace elements of T1. T2 and calcitonin plus a measure of T3 and a measure of T4 and the most ' fullest spectrum ' of thyroid hormone replacement that there is.

Did you consider sourcing an alternative brand of NDT ?

Did you feel better then - how much were you taking - you definitely need more than T4 monotherapy - why not source your own NDT if you can't anywhere through the NHS.

You will still need optimal conversion of the T4 element in the NDT which means you still need to build up your vitamins and minerals.

Your over range ferritin, needs to be checked out though, if maybe nothing as some people have Hereditary haemochromatosis and can resolve the issue by giving blood.

I'm with Graves Disease post RAI thyroid ablation in 2005 and became very unwell some 8 years later - and found this amazing forum - details on my profile page - and I now self medicate with NDT and am much improved.

40sgirl profile image
40sgirl in reply to pennyannie

Natur-thyroid was recalled because the potency was inaccurate. I did feel better with that but was put on Effra then, I just couldn't get on with that at all so chose to go back on Levothyroxine. Natur-thyroid was still not available, and to be honest I haven't felt too bad on 150mg of Levothyroxine. The problems got very noticeable when the dose was reduced to 125mg. However today I managed to get through to my Surgery and explained to a new Doctor the issues with my blood results and couldn't believe it when he said the ranges are only guidelines and one size does not fit all, whats normal for some will not be normal for you. He has written out a new prescription to increase my dosage back to 150mg providing I have another blood test after 2 months so that he can start a graph to monitor my results. I will be taking your advice about taking supplements as he agreed I should be doing given my age anyway. Would you be kind enough to advise what vitamins and minerals I should consider, what do you think about taking a probiotic?

pennyannie profile image
pennyannie in reply to 40sgirl

Well that's a bit encouraging - let's hope treating the patient and the symptoms continues and the TSH computer dogma stays on the bypass :

Is this the same doctor who cut back on your doses these past couple of years ?

Well there are numerous brands and it all becomes a bit of a minefield.

Why not start a new question asking forum members what vitamins and minerals are recommended and at what doses ?

You could also give feedback as to your phone call from the doctor and actually what is s/he doing about the over range ferritin ?

I consider Seaside Susie our very own dancing queen of the vitamins and minerals but all the admin include links to the vitamins and minerals reading materials.

I don't take probiotics do haven't an opinion on that but do supplement on a regular basis all the vitamins and minerals as detailed previously.

SlowDragon profile image
SlowDragonAdministrator

Looking at your age ….and the fact you have had dose levothyroxine reduced over several years, you’re highly likely to have low vitamin levels now

What vitamin supplements are you currently taking

Request GP test vitamin D, folate, ferritin and B12

Low vitamin levels are more common as we get older

For good conversion of Ft4 to Ft3 we need optimal vitamin levels

Which brand of levothyroxine are you currently taking

Do you always get same brand levothyroxine at each prescription

Many people find different brands are not interchangeable

Please add ranges on Ft4 and Ft3 (figures in brackets after each result)

40sgirl profile image
40sgirl in reply to SlowDragon

Thank you very much for your reply I will request a vitamin test from my GP , the Levothyroxine comes in the same packaging and have NorthStarX on the box, not sure if that's the manufacturers' name. I will put all the items you have raised together with the others suggested by your colleagues to my GP

helvella profile image
helvellaAdministratorThyroid UK in reply to 40sgirl

Look on the long side of the box. It will say PL Holder and the name of the company that is responsible for it. Effectively, the manufacturer.

The example is a pack of levothyroxine packaged for Almus but made by Accord/Actavis. (Sorry - the photo is out of date. The company has changed to Accord.)

Side of levothyroxine pack
greygoose profile image
greygoose

Hi 40sgirl, welcome to the forum.

Do you have Hashi's? Because that FT4 is so high, I cannot imagine that it was all due to 150 mcg levo taken over 5 hours before. It's too high, and looks more like a Hashi's 'hyper' swing. Pity they didn't do the FT3, which would have told us for sure!

And, it's difficult to believe that your FT4 would come down so much in one month, with just a reduction of 25 mcg - especially as your FT3 is so low. So, that looks like Hashi's, to me, and little to do with your dose.

The July results are showing very poor conversionj, and very low FT3, and that's why you're having symptoms again. It's low FT3 that causes hypo symptoms, not low TSH, and not high FT4. :)

40sgirl profile image
40sgirl in reply to greygoose

Thank you for your response, to the best of my knowledge I have never been tested for Hashi's, but will suggest to my GP I am tested for that at the same time as a vitamin test. If, as you suggest it is Hashi's then I will need to do some research as to what that entails because I am totally ignorant of it . In fact having found this site I cannot believe how lacking in knowledge for the last 35 years about hypothyroidism I have been.

greygoose profile image
greygoose in reply to 40sgirl

Well, Hashi's is the common term for Autoimmune Thyroiditis. Autoimmune Thyroiditis is actually two diseases: Hashimoto's Thyroiditis and Ord's Thyroiditis. The difference is that Hashi's usually results in a goitre, and Ord's results in a shrunken thyroid.

In Hashi's, the immune system attacks the thyroid and slowly destroys it, mistaking it for the enemy - no-one really knows why, although there are many theories.

During an attack on the thyroid, the dying cells release their stocks of hormone into the blood, causing levels of FT4 and FT3 to rise sharply, which causes the TSH to drop very low.

At the same time, the proteins Thyroid Peroxidase and Thyroglobulin, contains in the cells, and used to produce thyroid hormone, also leak into the blood, where they shouldn't be. So, Thyroid Peroxidas Antibodies (TPOab) and Thyroglobulin Antibodies (TgAB) come along to supervise its removal and destruction - like autoimmune cleaning ladies. So, these antibodies in the blood are tested in order to diagnose Autoimmune Thyroiditis. It's not a 100% reliable test, but it usually works. :)

SlowDragon profile image
SlowDragonAdministrator

Assuming test was done via Medichecks or Blue horizon or Thriva

Ranges are

Ft4 12-22

Ft3 3.1-6.8

So results show

FT4: 23.7 pmol/l (Range 12 - 22)

Ft4 over range at 117.00%

FT3: 3.9 pmol/l (Range 3.1 - 6.8)

Ft3 only 21.62%

Helpful calculator for working out percentage through range

thyroid.dopiaza.org

This shows very poor conversion of Ft4 to Ft3

Ideally both Ft4 and Ft3 should be at similar levels, at least 50-60% through range

Ft3 is far too low

FT4 is too high…as is not converting to Ft3

First step is to get vitamins tested and improve to OPTIMAL levels …vitamin D, folate, ferritin and B12

Are you vegetarian or vegan?

If GP won’t test, test privately

We always recommend getting FULL thyroid and vitamins tested once year …..usually that has to be privately (Medichecks or Blue Horizon)

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins

bluehorizonbloodtests.co.uk...

Helpful to know if you have Hashimoto’s, by testing thyroid antibodies too

About 90% of primary hypothyroidism is autoimmune thyroid disease, also called Hashimoto’s usually diagnosed by high thyroid antibodies

Approx how much do you weigh in kilo

Are you lactose intolerant and on dairy free diet or gluten free diet

40sgirl profile image
40sgirl

Thank you so much for your reply, I will follow this up with my GP but if necessary will get private test as well. I am not Vegan or Vegetarian but always eat plenty of fresh fruit and vegetables. I also spend many hours in my garden (Vitamin D)

SlowDragon profile image
SlowDragonAdministrator in reply to 40sgirl

You might be astonished how low your vitamin levels are…..even vitamin D

40sgirl profile image
40sgirl in reply to SlowDragon

Thank you SlowDragon I have decided to go with the Blue Horizon Premium blood test and see what that reveals, I doubt the GP would be able to argue or fob me off with that information.

SlowDragon profile image
SlowDragonAdministrator in reply to 40sgirl

Only do private testing early Monday or Tuesday morning, ideally just before 9am and last dose levothyroxine 24 hours before test

Only drinking water between waking and test

This gives highest TSH and lowest Ft4

Then take your levothyroxine after blood test

Come back with new post once you get results

tattybogle profile image
tattybogle

Hi . quick explanation :

TSH (Thyroid Stimulating Hormone) this is a message from the pituitary to the thyroid, asking it to make more (or less) thyroid hormone (T4 / T3). A higher number means 'more please'.

fT4 (Free T4/ Thyroxine) this measures the amount of T4 in your blood from the levo you take, (plus any your thyroid still makes) 'Free' means it only measures what is available to use.

Your very over range FT4 was the main reason why they reduced your dose

(Your TSH was also a little lower than they like, but they might have let you get away with that if the fT4 had been in range)

It's really unfortunate you took the test 5 hrs after taking levo, as there is a peak in blood levels from roughly 1-6hrs after taking the tablet (when it is absorbed from the gut ) .. by about 12hrs, the level has fallen most of the way back to your base level , and by 24hrs , you get a true reading of your real base level.

When discussing with GP .. make them aware that you took levo a few hrs before test. as your real base level if tested properly (after 24hrs) would not have been as high as it looked on that test . although it would have probably still been over range by quite a bit.

To compare your two fT4 results properly , you need to convert them to a '% through range' because the lab ranges are so different (calculator originalText )

FT4: 32 pmol/l (Range 9 - 26) 135%

FT4: 23.7 pmol/l (Range 12 - 22) 117%

When you do this you can see that the difference is not as big as it first seems.

Much of the difference between these two tests is probably explained by the time of taking the tablet. with a smaller amount being due to the lower dose. ( and as greygoose points out if you have autoimmune hypothyroidism it's always possible that your thyroid had dumped some extra T4 into the bargain, which had later gone down by itself)

Since the fT4 is still over range even with a 24hr gap and a lower dose ,your GP will probably be very unwilling to put dose back up . especially since the TSH is also so low .

There are reasons to avoid a high fT4 level if possible , possible links to proliferation of some types of cancer cell have recently been noted in research. .. so ideally rather than increase your T4 dose back again to feel better ,you want to try to improve your conversion of T4 to T3, and /or try to get some T3 prescribed by endocrinologist to replace a bit of the Levo you take . but realistically these options are not always possible.

If you argue your case very strongly and show you understand the (alleged) 'risks' you may be able to get GP to agree to put it halfway back up to 137.5mcg.

... (i used a study as evidence for discussion with GP which shows TSH between 0.04 and 0.4 had no greater 'risks' than TSH in range does .... please see my reply to this post (3rd reply down) : healthunlocked.com/thyroidu... .... it contains links to that study and several other useful discussions on the subject of low TSH / risk / quality of life )

I had the same problem as you with fT4 going very over range even though i felt ok , and GP reducing dose. from 125 to 112.5mcg then 100mcg straight after . The 112.5mcg dose was a bit naff for the first 5 weeks , felt undermedicated , but i'd then started to feel ok again ..... but fT4 was still high and GP wanted further reduction ...however i felt horrible on 100mcg my digestive system went to sleep . chronic constipation . zombie brain etc and that time it didn't improve as dose settled in .it got worse ....so after a lot of argument we agreed on 112.5mcg even though my fT4 was still over range.

After another 6 months on 112.5mcg my fT4 had come down by itself again anyway. My GP has written 'she understands the risks' on my notes to cover his back, which is fair enough.

I was surprised to notice after a few months on 112.5mcg my sleep was much better than it had been for years .. so i have kept dose at that level.

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