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Thyroid UK
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Endo is really confusing me re T3 dose - can anyone help please?

I have been trialling T3 since May this year via a private endo but through my doctor on the NHS. I went from 15, to 20, to 25mcg a day split into 3 doses and having blood tests every 6 weeks. As I still didn't feel well, he then told me to take 50mcg a day divided into 2 doses (I queried this with him as it was such a large increase), which didn't work for me as the gap in between was too large (he said 12 hours). He then told me to reduce to 40mcg (divided into 3 times a day - which I did) then have a blood test, with the possibility then of taking 45 (20, 15, 10). I am having the blood test on 29 November. I told him I didn't feel well on 40 but then realised I had been forgetting to take my Vitamin D, which I was extremely low in. When I started taking it again, I started to feel a lot better, which I told him.

He has now emailed me to say that I am taking far more T3 than he would advise as it can cause bone and heart problems. He, himself, asked me to get a bone scan done, which I did, and it was fine. He, himself has told me to take the 40mcg a day of T3.

These are my test results so far:

September 2013 on 50mcg

TSH 0.01

T4 12.1

T3 6

Blood Tests 23 July 2013

I am currently on 25mcg T3 and 100mcg T4. I've just had July test results back today:

TSH 0.01 (0.35-5.50)

T4 12.8 (10.50 - 20.00)

T3 4.7 (3.5 - 6.5)

In May the results (on 20mcg T3 and 125 T4) were:

TSH 0.01

T4 13.2

T3 4.8

I am so completely confused and don't know what to say to him. He has also asked to see me in December (we have been communicating via email since my first two visits to him, to save me money which was at his suggestion and for which I am grateful).

What is going on can anyone shed any light on what he is thinking please?

30 Replies

Your TSH is the same as mine and I am well. 40mcg isn't a high dose. With T3 if you feel overstimulated it is simple to reduce your dose next day.

When on T3 your T4 will be low so I think your blood tests are fine. He is talking rubbish about heart and bone problems. I link below an archived link (scientist died last year) who himself took T3 from the age of 19. His protocol of taking T3 is different from modern day Endos and his patients took T3 once per day and although it goes into your bloodstream quickly, the effect on our cells continue between 1 and 4 days.


Question: I’m a physician who has just begun using T3 in my practice. One thing I’m concerned about is the short half-life of T3. Shouldn’t patients divide their daily dose up and take part of it at least twice each day, or instead use sustained-release T3? It seems that this would allow the effects of T3 to continue through the day rather than stop midway or in the evening?

Dr. Lowe: The short time that T3 is in the circulating blood isn’t the limit of its beneficial effects on the body. When T3 binds to T3-receptors on genes, the binding regulates the transcription of mRNAs, and the mRNAs are later translated into proteins. The transcription and translation initiated by the binding of T3 to T3-receptors occur in waves, and these waves far outlast the T3 that started them at the chromosomes. Moreover, the newly synthesized proteins themselves far outlast the transcription and translation. As a result, a single dose of T3 will be long gone from the patient's system before he or she experiences most of the benefits of that dose—a molecular and metabolic yield that may smoothly spread out over one to three days



Thanks that's useful information. I just wonder if my doctor wants to stop me having it on the NHS and this is her way of doing it. I have read that some counties are doing this. I will use the information you have given me to fight my corner. Thank you.



Ps. I should have added that I am also on 100mcg T4 as well.


They should treat your symptoms & use the blood tests as ONE of the diagnostic tools available, not THE be all and end all of your treatment.

How you feel should be the gold standard. If your dose is being adjusted at your request then the right dose/combination has been found yet.


Katkin I was prescribed T3 3 x 20mcg daily prior to RAI. I self titrated between 60-120mcg per day and noticed neither benefit nor adverse reaction so settled on 60mcg.

There are people on this forum taking considerably more than 100mcg daily.

FT3 in the upper range, usually the top 75% quartile, is desirable for most people to feel well, especially if you're surgically or RAI induced hypothyroid.


Thank you Clutter. I just don't know how to get this over to the Endo though, who seems intent on decreasing my T3.



Write a short note explaining that you feel well on your current dose and do not wish it to be reduced. Give him the note when you attend.

State that although you do not agree such a low dose exposes you to the health risks he has indicated, you are happy to absolve him of responsibility, in writing, if he will continue your current regime. Find a new endo if he isn't prepared to listen.


Like you I'm seeing a private doctor and an NHS endo. Sometimes they forget what they've said. My endo forgot we'd talked about tweaking the dose so now my script is wrong. I was on 125 t4 and added in up to 25 t3 gradually, then my t3 went a bit high (I felt great, of course) so now I'm tweaking the proportions and at the moment I'm on 100 t4 and 30 t3. Thinking about raising the t3 a little because I'm having a rough time.

My doctor wasn't concerned about the suppressed tsh but didn't want my t3 to go any higher. I could have kept the dose the same for a little while considering how well I was. I don't think the damage is immediate, it's if your t3 remains high over time - ?

shaws is the expert here, not me, but as your doctor says there are potential risks to the heart and bones when the t3 is too high, and when my tests were progressively higher I was concerned that my t3 might continue to rise but I wouldn't realise it and it might do some damage over time - ? But I'm torn because, like you, being so near the top of the range did make me feel great. I had a few minor symptoms of being on a little too much but generally it made me feel loads better. So it's always on my mind now.


What other symptoms did you notice on too muchT3 please?? Ging


Sorry to say my loose bowels always gave the game away. :-) Now I can't even tell if I'm hyper or hypo. Pulse and temperature are meant to guide you, but my temp is usually low even when my pulse is high.


T4 can cause loose bowels/explosive diarrhoea in some people.


I don't believe there is danger to heart &/or bones when FT3 is within range. I think recent research disproves this. Sorry I haven't links I can attach.


Yes, of course you're right. I was rereading this thread and I see now that the OP was within range so I don't know what the doctor was worried about.


Anyone would think endos hate their thyroid px feeling well. As soon/if ever they do, hey let's meddle with their meds.


When on thyroxine or t3 your tsh will be suppressed because the pituarity thyroid axis is satisfied

40mcg of t3 is not a high dose my husband was on 120mcg but is now well on 5 grains armour a day as are other hypo friends

my daughter is on 80mcg t3 plus 275mcg t4 and far from well

grandaughter is on 50 mcg thyroxine and is worse not better

bottom line is thyroxine and t3 are chemical and synthetic and for many people are sheer poison

when will the medics face the fact natural dessicated thyroid is far far better


Thanks reallyfedup123.

It does seem that some people do not tolerate the additives in NHS T3 very well and perhaps this is me. I have now read that it contains metholated spirits! I haven't experimented with other makes of T3 or NDT yet as I don't work and am worried it will be very expensive. The irony is, I gave up work because I couldn't cope. At the time all I was given was Levothyroxine and no one mentioned T3 to me. It was only through reading whilst at home that I realised there was an alternative. I am now hoping to go back to work, but wont be able to if my T3 is reduced.



have now read that it contains metholated spirits!

I can't imagine this is anything to be concerned about, but why not contact them and ask why this is listed an ingredient in our T3 medication?


+44 (0)20 8588 9441


1 like

I have sent them an email re the methylated spirits and lactose. Lets see if they bother replying.


Good… let's not hold our breath waiting for anything useful to come out of it, but if you don't ask… :D :D


I've had a reply!!!!

I'm not quite sure how to reply. Any ideas?

Thank you for your enquiry regarding our product Liothyronine 20micrograms Tablets in which you enquired about why methylated spirits and lactose are present as excipients in this product.

The Summary of Product Characteristics (SmPC) states the excipients in this product to be:

6.1 List of excipients

Lactose BP

Maize starch BP

Acacia powder BP

Sodium chloride BP

Magnesium stearate BP

Industrial methylated spirit BP

Purified water BP

As confirmed from our Quality Department, methylated spirits is used during the manufacturing of this product, however this is fully removed during the drying process and no concentration is present in the final product.

Lactose is used in this product as a filler and is derived from the milk and calf rennet of healthy animals. There is no risk of transmissible spongiform encephalopathies (TSE) contamination.

As part of our drug safety responsibilities, could you possibly confirm if you or anyone you know has experienced any unwanted side-effects? If so, we may pass the details on to our Safety team for assessment. All the information provided will be kept strictly confidential and may be used to help patients or healthcare professionals in similar situations. If so, the safety team may contact you for further information.

I hope that you find this information helpful.

Yours sincerely,

Rebecca Galloway

Medical Information Scientist


1.Summary of Product Characteristics – Liothyronine 20micrograms Tablets. Can be viewed on medicines.org.uk/emc

On 15 March 2013, the Amdipharm and Mercury Pharma groups of companies (including their Antigen, Anpharm, Forley and Goldshield affiliates) merged to create the new international speciality medicines company, Amdipharm Mercury Company Limited. This merger will allow us to further improve the service we offer to partners and patients, and to make our combined product portfolios available to a larger number of patients. However, rest assured that there have been no changes to the manufacturing formulation, strength or pack sizes of any of our medicines, nor to any of our legal and regulatory duties.


T3 does indeed contain methylated spirit and its enough to affect anyone who is chemically sensitive

i cannot even open a bottle of methylated spirit or nail varnish or paint in same room as my husband as he can become extremely ill

i spent far far too many years from age 28 watching his suffering through graves disease, thyroidectomy , 12yrs untreated with hashimotos then on thyroxine and t3 and only on armour is he now fit and well age 72 so there will be one hell of a fight if they try to stop that


As your TSH is very low, all of your T4 is going to convert to Reverse T3 which will block out the T3 you are taking and stop it from working. You would be much better stopping all T4 and just take your T3 because at least then it stands a chance of working for you. I was in a similar situation until I stopped the T4 and now I am feeling so much better on just T3. I can recommend Paul Robinson's book "Recovering with T3 ", which helped me to understand the influence that TSH has on the whole thyroid world. I have never looked back since going on to just T3, I've now lost 3 stone in weight, I can play at least 6 hours of tennis a week and my brain has come alive again. If you do decide to stop taking the T4, it will take at least 14 days to come out of your systems, so give it plenty of time. Good luck



Thanks Heather. What dose of T3 do I take if I stop my T4 do you think?

Best wishes



You may find a T4 + T3 combo more beneficial than either monotherapy. If you FEEL good stick with your current regime. If not, try 50mcg T4 + 50-60mcg T3 for two weeks then adjust again. Remember, it will take 8-10 days for the T4 to clear your system & a matter of hours for T3 to kick in so you may want to take it slowly. It's a bore fitting meals & other meds around multiple doses of T3 unless you can persuade your endo to prescribe time release T3.

Society of endos has just come out against T4 + T3 combi until there is more published evidence on the benefits, so expect entrenched opposition.


Thank you Clutter. Why on earth have the Society of endos come out against T4 + T3 combo? Surely this is a step backwards? Are they thinking that we all go back to T4 only?


Maybe. The majority of people either do well on T4 monotherapy, don't complain if the do not or accept spurious suggestions that their illness is 'probably not thyroid related'. There seems to be an inability to consider that thyroid related issues are not purely related to the thyroid gland and circulation of thyroid hormone but also the conversion and utilisation of thyroid hormone at a cellular level.

50+ years ago T3 was prescribed for JFK. It seems inconceivable that there is insufficient published material in all that time proving the benefits of T3 in combination with T4 or solus. It's estimated 20% of of patients do not do well on T4. That's thousands of people in the UK and hundreds of thousands world wide. It's scandalous.


I would stay on the same dose of T3 until most of the T4 has left the system, say at least 14 to 21 days and then see how you feel. The "normal full replacement" dose is 60 mcg, but everyone is different. I am now taking 105 mcg split into small doses throughout the day, which is right for me but you will have to see how your body responds. Only increase the dose in very small steps -say 10 mcg- and then wait about 4 weeks before you add any more. Its a hard step to stop taking T4 but its given me my life and brain back again. The NHS drs are very reluctant to take this step and certainly won't prescribe more than 60 mcg daily.

Good luck,



Thank you


Heather, did you have a period of good health on t3+t4 and then decline? Or did it just never work for you?

I had a wonderful two month period of wellbeing on t3+t4, then became technically hyper (still felt well) and then I suddenly felt hypo and rubbish. I began to reduce my t4 and felt horribly hypo within days and when I reduce my t3 I feel even more hyper. I'm going to buy that book immediately and see if it can address what is happening to me as I just get more confused and helpless as this situation develops.

I've sent you a pm.


One thing at a time ALWAYS otherwise you'll yoyo dose and never know what is good. At the point you became tech hyper d'you mean the blood test said so, or you felt so? The easiest way to adjust is surely to stick with the T4 (storehouse) dose and titrate the T3 which is the active hormone with a half life of hours, so not difficult to adjust up or down to suit.

It is quite feasible to experience hyper feelings when you are undermedicated on T4.

If you've been supplementing vits and minerals, improving adrenal support may improve absorption and conversion of your thyroid replacement and you may indeed be overmedicated.

Weight fluctuation will affect dosage and cold weather affects many hypothyroid sufferers.


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