Is this dose of 5mcg of T3 likely to be effecti... - Thyroid UK

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Is this dose of 5mcg of T3 likely to be effective or is my Endo placating me?


Went to see Endo on Monday for 4th time-always a joy! Had the usual lecture of "not all your symtoms are thyroid based the remaining ones are because you are menopausal/have chronic fatigue syndrome/are a couch potato/are depressed or anxious" (who wouldn't be!) I have classic thyroid symptoms and finally, after I agreed to make an appointment with a psychologist because of my" inability to accept that my symptoms may not be curable" he agreed to let me try a T3 T4 combo.He has dropped my Levo to 100mcg and added 5mcg of T3. Does anyone know if such a low dose is likely to have an effect or has he just given me a small dose to shut me up & make me go away. I am not seeing him for another 3mths so I don't want to wait for my next appointment if this is not likely to work. Thanks

35 Replies

If he dropped your levo by 50mcg he should have given you at least 10mcg of T3.

Do you have a print-out of your latest thyroid gland blood tests, with the ranges, that you can post on a new question for members to comment.

Your Endo sounds exactly like an awful lot of unsympathetic/unfeeling supposed to be physicians.

Even Dr Toft has a paragraph (which I will miss out) in the extract below but Lyn Mynott of has already written to complain to Dr Toft but it appears to be endemic amongst most doctors when all we want is professionalism:-

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/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).

Even while taking the slightly higher dose of levothyroxine a handful of patients continue to complain that a sense of wellbeing has not been restored. A trial of levothyroxine and tri-iodothyronine is not unreasonable. The dose of levothyroxine should be reduced by 50µg daily and tri iodothyronine in a dose of 10µg (half a tablet) daily added.


You can email and ask for a copy of the Pulse Online article and send it to your Endo. Highlighting question 6.

Maybe your Endo/Psychologist would also like to read the following article:-

lynn0857 in reply to shaws

Thanks for your reply. My Endo seems to be a nice bloke on the face of it but is obsessed, as most NHS doctors seem to be, with trying to blame the symptoms on anything other than thyroid. Why is this? He can't understand why I take a folder of information & a notebook & pen to every appointment and commented that I am always very stressed whenever he sees me! My Levo was 125mcg/150mcg on alternate days before Monday.My last blood tests were TSH 0.15 (it never reflects what is happening at one point it fell from 1.8 to 1.3 and my FT4 fell from 16.5 to 13). My FT4 was 19 (range 12-22) and I don't know my T3 because the lab decided not to do it again ( this is the third time) because my other tests were in normal range.

May I ask what your levo dose was before he dropped it to 100? My doc didn't want me to drop my levo until well after I began to feel well with the addition of 10mcg t3.

If you were on 125 for example you are likely to go hypo on 100 + 5mcg t3, or at least in my experience that would happen.

If this (above) was the case, if I were an uncharitable person I would say this has been calculated to make you feel worse on t4+t3 but call me bitter. :-) To be fair I don't really have enough info to make that kind of judgement so feel free to correct me. x

PS. My reply crossed with shaws above, thus the duplicate questions. When I dropped my levo, despite replacing with supposedly enough t3, I went hypo, so I do not believe that the formula of 1mcg t3 = 5 t4 is as straightforward as that. If you're adding in 5mcg t3, unless your bloods are already right up against the top of the range or you're very sensitive to it, you may go hypo if they reduce your meds. x

Thanks for the reply. I was on 135mcg of Levo before Monday so it has been reduced by 35mcg & replaced with 5mcg of T3. I have been given 20mcg tablets which I am supposed to cut into quarters so I could self medicate & take more if necessary. My TSH doesn't give a true reflection of what is happening. At one point TSH fell to 1.8 and FT4 fell to 13 (ref. 12-22) I only have one FT3 result from the NHS 4.7 (ref. 3.1 -6.5) the lab haven't bothered to do it the other 3 times that it's been requested. My FT4 has been up to 19 since I have been on the 135mcg of Levo.My Endo asked why I am always so stressed whenever he sees me - 3 guesses!!!

I'm glad you asked this and will be following the replies!

My endo put my on 5mcg of T3 a few weeks ago and dropped my Levo down from 225mcg/200mcg (alternating days) to just 200mcg daily plus the T3. The first 2 days I really thought I was feeling better, but after that just slumped and back to feeling awful again :-( (not helped I don't think by my shoddy cutting of the pills!)

Marz in reply to Penny_babe2001

You can buy pill cutters very cheaply at the chemists ! If there are any crumbs - then dampen your finger and gather them up :-)

Penny_babe2001 in reply to Marz

Ah yeah, I got a cutter now. But I thought I'd make it quicker for myself when I first got the pills and cut up a few and put them back in the bottle. Hindsight is a beautiful thing ;-)

I think that you lose half of the pills to dust when you cut them!

Marz in reply to lynn0857

Give it a FIRM and hard punch downwards - mine are fine ! ....most of the time ;-)

HarryE in reply to Marz

Is that the pills or the endo???? ;-)

Marz in reply to HarryE

You could try your Endo next time ! But don't dab your finger to gather up the debris :-) x

lynn0857 in reply to HarryE

That made me laugh, I would love to give the Endo a good punch downward!!

HarryE in reply to lynn0857

I'm sure it would be very satisfying :-D

shawsAdministrator in reply to Penny_babe2001

I have a very good pill cutter but, again, trying to cut them into quarters is nigh impossible. At most you will not have an accurate dose but I judge that it will work out by the end of the week.

jaijai96 in reply to shaws

I use a craft knife!

I'll give it a try, thanks.

My GP agreed to let me try T3, starting at 5mcg, and dropping my T4 from 112.5mcg to 75mcg at the beginning of December.

I gradually felt worse, even after increasing to 10mcg T3 after 2 weeks.

Did a reset with my GP in January, then started on 20mcg T3 with 75mcg T4 at the beginning of February and began to feel better after two weeks, but there is still plenty of room for improvement.

I suspect that the drop in T4 was greater than the positive effects of the T3, so you may also experience this.

It is not just inconsistencies with diagnosis that we have to endure, but also different views on the T4 to T3 dosage equivalence.

My GP says that it is 5:1, whereas i have read that it is 4:1, or even 3:1 in different reports/papers.

T3 is available in bottles of 100 5mcg tablets manufactured by Paddock Labs and supplied on prescription by Boots.

This has given me the flexibility to experiment a little with doses and no need to cut the tablets.

lynn0857 in reply to Parbrook

Thank you for that. I had already decided that I was going to find the right level for myself. I could be waiting for years if I depend on the Endo to sort it out! I have some extra Levo & I think I can fiddle the T3 around so that I can experiment with that too. Surely that has got to be better than suffering on the wrong level of medication for the next 3 months. Good luck!

Parbrook in reply to lynn0857

Do you have your FT3 and T4 blood results?

Knowing if your FT3 is low and your T4 is high or low will help to make informed decisions on managing your medication.

Note that the effects of an increase in your T3 dose will be quicker than the effects of a reduction in your T4 dose, so I suggest that you be careful about when you make changes (probably 4 weeks minimum, unless things are really bad).

I experienced a short period when I felt a little over-medicated, because the effect of a reduction in T4 can take 4 weeks, whereas the effect if increasing T3 can be felt from between 2 days up to 2 weeks.

lynn0857 in reply to Parbrook

I do not have a T3 result, the Endo asked for one but the lab didn't do it because my FT4 was at 19 ( ref 12-22).this is the 3rd time that this has happened. I'm not sure how these lab people can make a decision of this kind but it seems that they do.

Parbrook in reply to lynn0857

Sounds like you need to get your Endo to hit the phone and insist that the the lab does your FT3 as it is currently preventing him/her carrying out a proper diagnosis and medication plan. It is important, especially as you are now taking T3.

If you are not converting T4 to T3, then it is absolutely necessary to know your FT3 result and it may also explain why the T4 is not working very well.

lynn0857 I agree with yousurname, but surely now that you're on t3 they will have to test it. Doc who is ordering the test needs to write on the form that you're taking liothyroinine. This should work (or at least it did for me).

Let us hope so, I will be sure to mention it when I book the tests.

Yes, if you have the opportunity, ask the doc, ask the receptionist, ask the phlebotomist (double-check with everyone), make sure it has been specified on the form and ensure the phlebotomist knows they need to take enough blood. If you're on the ball you have a better chance of getting it done properly. Annoying but true.

Our excellent phlebotomist apparently failed to take enough blood once, though in my bitter, cynical way, I suspect that the labs reject the test for all kinds of reasons hoping no one will notice so they can avoid doing it at all. The labs are now the biggest hurdle somehow.

Good luck! Hope you get it done at last.

I have my blood taken in the Endo ward at the hospital by an Endo nurse. The tests were clearly marked on a yellow slip ( evidently that is important for unusual test requests). The nurse was aware that I needed T3 results but the lab made the decision not to do it. Very frustrating! I don't know who they think they are.


In that case I take it back - if you're on the ball you have no better chance than if you're not!

Btw I didn't mean to imply that you were previously not 'on the ball' and could have chosen the words better. I thought I had got results at the local surgery because the phlebotomist was on my side and after I had pestered everyone she made sure all their ducks were in a row, but in light of your experience it looks like if the lab had then vetoed it she would have made no difference.

I wonder if it is down to the small dose. Perhaps they have a cutoff dose of 10mcg or something.

Do you know how you will resolve it?

I wish I knew, it seems that we are in the lap of the Gods. My friend who is a healthcare expert says that there are some very large egos in the hospital labs & the doctors have to keep them happy otherwise they don't get their results back quickly. Our wonderful NHS eh?!


I actually paid for a set of thyroid function tests including T3 to prove to the GP that I needed to see an Endo. She had requested the split hormone tests twice and again the lab did not do them because TSH was in "normal" range. I'm finding more & more that you have to pay if you want a decent health service. Why did I pay National Insurance for 30 years again? :)

I hear you. :-)

I have just got my first ever T3 results. I asked the GP to flag it up and reminded the nurse to highlight it and wonder of wonders the lab did it! ....and it is below range so I have had my dose increased :)

Fantastic! You must be so pleased (not pleased to be ill but pleased that finally someone has done the test and now you can fix what's wrong). x

Thanks, yes I am feeling hopeful :)

Well done you! Maybe I will finally get a result on the NHS next time I see the Endo - they don't have to avoid it now that I am on T3 anyway , or am I just being cynical?! I'm not sure that the results make a difference anyway as the doctors don't seem to know how to put things right when they have them.

The late, great Dr Skinner used to prescribe on symptoms alone and he cured many patients that were failed by the NHS. If anyone out there has not read his book "Hypothyroidism Diagnosis and Management" you must read it - it's essential reading for all thyroid sufferers. I read it in a weekend, it's easy reading & I was laughing out loud at his wicked sense of humour!

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