Thyroid UK

Can anyone throw any light on why blood results are so different

I was on same doses of both t4 and t3 . Blood draw was same time too.

08/06/17 75mcg Levo + 15mcgs T3

Tsh 0.42 (09-19)

Ft4 10.8 (9-19)

Ft3 3.2(2.6-5.7)

Last dose t3 7.30 am gap of 25hrs

Results 9/11/17 75mcs Levo 15mcgs T3 at 7.30

Tsh 1.83(0.35-4.74)

Ft4 10(9-19)

Ft3 2.8(2.6-5.7)

Last doses were 7.30am previous day gap of 25hrs

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130396,

Possibilities are:

1. Your thyroid function is declining so FT4 and FT3 have dropped and you need more T4 or T3.

2. Thyroid levels drop during the autumn and winter and TSH rises.

3. A bit of both.

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Hi Clutter

I had lowered my t3 from March when I was dosing t3 higher.

I was trying to stop my hard heartbeat and it did work.

I didn’t have the hard heartbeat in June ( but that I remember having it)

But it’s now returned along with an aching shoulder muscle

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130396,

November FT3 is lower than June FT3 so perhaps you should increase T3 dose.

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I don’t understand it though!

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130396,

What don't you understand?

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I don’t understand why, when I’ve been taking exactly the same dose, there would be such a difference?

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130396,

I suggested above that it is either due to thyroid function getting worse or the fact that TSH is higher in autumn winter or a combination of both.

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Ok thank you.

I’ve never altered my dose in the winter even though I’ve been UAT for over 33 years

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130396,

Well you need to consider raising it now.

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I worry about getting RT3 if I raise it back up again .

I had an RT3 test done with Genova last year and it came back at 31. Top of their range was 54.

I was told it was high RT3 and it should’ve been 17.

I don’t understand why I was told that when top of range is 54 according to Genova

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130396,

31 isn't high if top of range was 54. Whoever told you that doesn't know what s/he's talking about.

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I was told that by someone on the Thyroud Advocates site who go by what STTM day.

She said converting it to how they would work it out Rt3 should be no higher than 16.

She said because mine was high that was why I was getting the HARD heartbeat

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130396,

31 can't possibly be high when top of range is 54.

It's nonsense to say that rT3 should be at a certain level. If it is within range it is fine.

Some of these fora talk an awful lot of guff about rT3.

tiredthyroid.com/rt3-3.html

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Thank you so much Clutter.

I do sometimes wonder if these Americans go over the top.

Do you agree that when on combo Ft4 should be mid range and ft3 should be top 1:4?

I think if I had mine in those ranges my tsh would be totally suppressed.

When I was on higher doses my results came back that’s tsh was <0.03 (0.35-4.74)

I can’t temember what my other numberswere but can find out.

Many thanks for your continued help

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130396,

No, I don't agree FT4 should be mid range and FT3 in the top quadrant. FT4 is often quite low in range when taking T3 direct. Most people feel well when FT3 is in the upper third of range but if you feel overmedicated then you need FT3 lower, perhaps halfway through range.

The higher the doses you take the higher FT4 and FT3 are likely to be and the lower TSH will be.

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It's highly unlikely that high rT3 would affect your heart beat. As Clutter said, a lot of people talk a lot of rubbish about rT3.

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Sorry above should read “no higher than 11”

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130396

What is the actual range for the Genova rT3 test you did?

Looking at their website, sample report for this test gdx.net/uk/product/reverse-t3

It shows the range as 0.14-0.54nmol/L, so if your result was actually 0.31 then you are less than half way through the range.

Whoever Thyroid Advocates are, are they using the Genova range or some other range because ranges aren't universal.

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SeasideSusie,

Thyroid Advocates is a new charity. I think it's run by Lorraine Williams who was active in BTF London.

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Thanks Clutter, that's the first time I've heard of them.

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SeasideSusie & 130396,

I got the wrong name. This is the new charity thyroidtrust.org/

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Clutter

The Thyroid Advocates group I got the information from is an American group run by Ellen Wilde so I think it must be a different group to the one you have said.

It’s a Facebook group

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130396,

Thank you.

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Can you tell me why Ft4 is lower even though my dose is the same?

I wanted to know if it’s lower, what is it converting to if I’m taking the exact same dose!

Thank you

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130396,

I've said twice already that it is probably due to decline in thyroid function. Lower FT4 means there is less T4 to convert to T3 and your FT3 is lower. You need to increase Levothyroxine or T3 dose if you feel hypothyroid. If you feel well there is no need to do anything.

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Hi Clutter

I know you’ve already told me the above.

Maybe I’m not putting the questionright.

I’m just wondering if I’m still taking same dose of t4 why it doesn’t stay the same Ft4.

Where is it going?

Obviously not to t3 as ft3 is low!

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130396,

If thyroid function has declined it means that your own thyroid is producing less so you will need to increase Levothyroxine dose to raise FT4.

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Hi SeasideSusie

Thyroid Advocates is an American group.

The ranges you stated above from Genova are the range mine was from.

The American group converted the units into their units and said mine should be 17.

The American group are based on STRM information and state for their units Rt3 should be no higher than 11.

So you’d say mine was ok.

At the time of my test I was taking 75mcgs t4 plus 25mcgs t3 (t3 split into 3 doses)

Thank you for your help. I appreciate it very much

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130396

I really wouldn't worry about it. You have the range, you have the results of where you are in the range, and you have the graphic as well as the numbers and you can see that you are less than half way through the range. It doesn't need converting to anything else, just go by the range of your test and where you fall within that range.

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Do you have Hashimoto's? Diagnosed by high thyroid antibodies

Also recent results for vitamin D, folate, ferritin and B12. Post results and ranges if you have them

Usually recommended to leave 12 hours between last dose T3 and test

24 hours for T4

Your results show you are very likely under medicated.

Personally, even taking T3 I find I still need FT4 towards top of range

Dr Toft, past president of the British Thyroid Association and leading endocrinologist, states in Pulse Magazine,

"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/l.

This 'exogenous subclinical hyperthyroidism' is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l)."

You can obtain a copy of the articles from Thyroid UK email dionne.fulcher@thyroidUK.org. print it and highlight question 6 to show your doctor.

Prof Toft - brilliant article just published

rcpe.ac.uk/sites/default/fi...

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Thank you for your reply

My B12 is 953(150-800)

Folate is 17(3-22)

VitD 101

Ferritin is apparently really good according to my Haemo who I saw today . He said it’s 3/4 of range.

I am on combo so as I understood it, when taking T3 as well it would lower Ft4.

I had a 25hr gap from last doses as I take both t4 and t3 in the morning.

I don’t understand how there is so much difference between the two when doses were the same and same gap from last dose to blood draw.

I’m worried if I increase doses I’ll get RT3!!!

Which I’m not sure I believe is a problem if it is within the range that Genova outline.

Last time I had Rt3 tested it was 31 and top of rangevwuth Genova is 54.

So based on that would you say my Rt3 was ok?

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Slowdragon I forgot to say I do not have Hashimoto’s. Sorry

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I think you need an increase in T3 because on both tests FT4 and FT3 were at the bottom of the range when they should be towards the top end.

T3 is the only active hormone and is required in our millions of T3 receptor cells to enable our body to function optimally.

You obviously needed an increase in thyroid hormones as FT4 dropped in second test. T4 - levothyroxine - is inactive and its job is to convert to T3, so you either need an increase in it or more T3.

Our blood tests aren't always identical they can change throughout the day but the best and easiest way to know if you dose suits, is how 'the person feels'. If unwell you need an increase, if you feel overdosed, you need a reduction.

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I lowered my T3 doses for these two results as I’d been having a very hard heartbeat.

It did stop after I reduced from my previous dosage earlier in the year.

However, it’s come back again over last couple of weeks.

I can put my previous results in here from earlier in the year with the doses ( when I had the hard heartbeat)

I worry about RT3

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There's no need to worry about RT3. The reason being that some people talk about it without really knowing much especially doctors.

This link is from an archived site and Dr Lowe was a Scientist and expert on Fibromyalgia etc and was one of our Advisers before his untimely death. Because he was also a very knowledgeable person and due to people being denied anything but levothyroxine and being refused prescriptions for NDT (due to rumours about it) - even though it has been used since 1892 in various forms and prevented people dying) he developed his own one which doesn't need a prescription.

This is what he said about RT3 - in the second answer:-

web.archive.org/web/2010103...

Dr Lowe had thyroid hormone resistance and took T3 only himself.

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Thank you Shaws

So is he saying that it doesn’t matter about having rt3?

I’m not very good at understanding technical things.

Can you explain it to me in terms I’d understand please

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I believe he is stating that it is not a huge problem.

I am not medically qualified nor a scientist but as far as I understand it, levothyroxine is T4, it then (in the body) changes to RT3, which in turn changes into T3,T2, T1.

If we take T3 ((not T4) it doesn't require any conversion as it is the only Active hormone required in our receptor cells.

He goes on to say:

Under normal conditions, cells continually convert about 40% of T4 to T3. They convert about 60% of T4 to reverse-T3. Hour-by-hour, conversion of T4 continues with slight shifts in the percentage of T4 converted to T3 and reverse-T3.

Under normal conditions, the body eliminates reverse-T3 rapidly. Other enzymes quickly convert reverse-T3 to T2 and T2 to T1, and the body eliminates these molecules within roughly 24-hours. (The process of deiodination in the body is a bit more complicated than I can explain in this short summary.) The point is that the process of deiodination is dynamic and constantly changing, depending on the body's needs.

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No, that's not quite right. RT3 cannot change to T3, but it's converted to T2, just as T3 is.

130396, you will only have excess rT3 is you have too much unconverted T4 in the body - or, as Dr Lowe explains, your are ill or starving, etc. Your FT4 is very low, so not much chance of that converting to rT3.

There is always some rT3 in the body, but even if it's in excess, it doesn't matter. It's only in the blood for a matter of hours before it's converted to T2, and as far as we know, is inert, anyway. So, you really don't need to worry about it, but you do need to have your FT3 at a decent level - T3 cannot convert to rT3, under any circumstances. Your T3 is too low, and that's why you have symptoms, not because of any rT3 you might have.

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Thank you greygoose.

I kept being told that my HARD heartbeat was because my rt3 was high at 31. Top of Genova range was 54!!

I was told to reduce my meds either t4 or t3 to get rid of Rt3 so I reduced the t3.

And I thought with my Ft4 going down it was because it was converting to rt3. It had me very worried.

I am not sure which one to increase now, t4 or t3

Thank you so much for your reply

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Reducing T3 definitely will not reduce rT3! Just make you feel worse. You've had some very bad advice, there. If I were you, I'd stay well away from that forum in future.

If the top of the rT3 range was 54, then these people were ignoring the actual range, and assuming that you can just take any old range and use that. It does happen that people assume that. But, you can't. Your rT3 was not high, and even if it was, it wouldn't have affected your heart.

I presume that you first added in the T3 because you were a poor converter. In which case, you probably are still a poor converter, so not much point in increasing the T4. You need to increase the T3 back to where it was.

T4 is often low when taking T3, because the body only hangs on to what it needs. It only converts to rT3 if it gets too high in range.

So, forget the rT3 and increase your T3 back to wherever it makes you feel well. Try taking magnesium malate to see if it calms your heart. But, also, get your potassium checked. :)

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Thanks again Greygoose

I do take magnesium bysglysinate 650mg a day.

I have had potassium checked and it’s within tange too.

So, I definitelyneed to increase t3 and leave t4 as it is.

Thank you so very much !!

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That's rather a lot of magnesium. It's usually recommended to take 350 - 400 a day.

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Hello Greygoose

So you think I should increase my T3 only and not increase T4??

The only symptom I really am concerned about is my hair!!!!

It has got really really thin especially on the top. I’ve got a very shiny scalp now that is hard to hide now. Would that be because my ft3 is too low?

Why do these American sites put so much on to rt3 and Paul Robinson says about it too.

What would be the signs of too much t3?

Can you advise on how I should now dose please?

At the moment I take both t4 ,75mcgs & T3, 15mcgs together in the morning on waking. I am never tired. My weight has stayed the same for last couple of years

Thank you so much for all the help you give to me

With thanks, Rose

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This thread was started a month ago. Has anything changed, since?

Your FT3 was very low, but if you feel well on that, and don't have symptoms, then leave your dose where it is. You are a long, long way off having too much T3 according to the above results.

Who knows if your T3 level has affected your hair. It could be due to many thing. Low iron, for example. Have you had your iron tested?

It used to be thought that rT3 was a problem because it blocked the T3 receptors, stopping T3 getting into the cells, and thereby keeping you hypo. This has since been refuted, and they've found that rT3 has its own receptors. But, the news doesn't seem to have travelled very far! RT3 is inert, so it's unlikely that it causes any problems.

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Hello Greygoose

I have come back to this post as I saw a dermatologist about my hair loss yesterday.

He said I had no inflammation and no scarring.

He said possibly my thyroid was causing it but as he’s not familiar with thyroid problems to speak to my Dr.

I have an appointment with my Gp tomorrow, so thought I’d get back to this here and see if you have any thoughts on what I should do?

My ft3 is the lowest it has been except when in Levo only and st that time my Ft4 was 22(9-19)

Ft3 was 2.6(2.6-5.75)

What would your thoughts be?

I am not iron deficient. I see a haematologist every 3 months and at my last visit my ferritin was 109

Many thanks

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OK, so those results show you have a definite conversion problem. So, absolutely no point in increasing your T4, that is clear. So, it seems that the next thing to try is increasing your dose of T3. There's no guarantee that that will help with your hair, but it's worth a try.

You'd need to give the T3 time to work, and you might need further increases - T3 can be increased by 5 mcg every two weeks until the FT3 is top of the range. But, if that doesn't work in, say, six months time, the next thing to do would be to get your sex hormones tested.

But, I have to say that not everybody gets their hair to regrow. A lot of people on here have problems with their hair, and it's very difficult to find the cause.

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Low T3 can cause heart problems. My ectopic beats get less troublesome when my T3 is higher.

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Thank you Angel.

I was put on Bisoprolol for migraines and I had hoped that it would also stop hard heartbeat but it didn’t.

It wasn’t so hard when I reduced t3 dose but I’m still breathless on exertion and oh my.... hair is getting so thin I can see my shiny scalp

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Your results are very very low, so certainly you need an increase. The rule of thumb is you want your freeT3 in the top third of the range. At the moment yours is rock bottom. RT3 is definitely not something to worry about when you are extremely undermedicated as you are now.

To answer your question about how things can change, the first thing to notice is that there are five months between tests. That is a pretty long time, and all kinds of things could have changed. Perhaps you've gained or lost a little weight, maybe your activity level has changed a little, maybe things have altered elsewhere in your body, you've had a cold or you've gained a little muscle, or allergies or some other health issue has flared. Or maybe you're eating a little differently or being exposed to more cold. These tests are impacted by every little thing that happens in your body.

There are also a few specific thyroid possibilities, if you've got thyroid antibodies they may be acting up or your thyroid function has declined, also its very common to need an increased dose over the Winter. Also, at the time of the first test you'd quite recently had a dose reduction. It may be that your body is increasingly struggling to cope with the very low dose. In this case you've left yourself with very little hormone about 7 months, so it's not surprising that things will be getting worse and worse, every tissue and organ in your body needs this hormone.

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