Should I continue to try for T3 only or up my T4 dose again?

Hello again,

Sorry for the many posts recently, I'm just feeling dreadful and trying to work out why and what to do.

So, basically, I felt like I got no benefit from T4 when on it alone. When I added in T3 I started feeling much better. Over the last year I have been (under he supervision of NHS endo) slowly raising T3 amount and dropping T4 amount. This was all going well until recently when my symptoms (exhaustion & depression mainly) returned.

However, I was thinking my symptoms were down to an increase in my working hours and duties, but I just can't be sure and I'm seeing the endo on Thursday and don't know if I should forge on with my plan for T3 only or stop and go back to a higher dose of T4, lower dose of T3. I would really appreciate some advice.

Has anyone gone on T3 only and found they needed to add T4 back in?

Why would a combination be better if T3 is the active form?

I just don't want to go backwards, find that doesn't help, and then have to spend even longer getting to T3 only, when I'm pretty close to it now, or to mess about with my meds going up and down. But at the same time I don't want to quit my job (which is the point I'm at) and then find out it was down to my thyroxine levels.

Here's the last 3 blood results with doses :

(My Dr won't test FT3 btw)

My TSH is less than 0.01 and has been for the last 18 months

20/03/17 FT4 9.2 (Range 9 - 21) TT3 1.7 (Range 0.9 - 2.5) On 75mcg T4, 25mcg T3

18/05/17 FT4 8.7 TT3 1.9 On 75mcg T4, 30mcg T3

20/07/17 FT4 9.2 TT3 2.3 On 75mcg T4, 35mcg T3

2/08 /17 FT4 7.4 TT3 2.4 On 50mcg T4, 40mcg T3

These results are all taken after fasting and at 9.00 in the morning, having not taken T4/T3 for over 12 hours.

I take my T4 in the morning and take the T3 in 4 divided doses throughout the day (morn (between 7.00 and 9.00), 12.00, 2.00, and 5.00). I may change the routine of that in future but as that's how I've been doing it from the start I don't think that's causing the new problems that have developed.

I've been trying to work out when I really started feeling bad and it's hard to tell, but it got really bad near the end of August - around the time my hours and duties increased, but also a couple of weeks after latest T4/T3 meds change.

I have been given advice on vitamins and diet but the lovely people who have commented on my previous posts, but before seeing the endo I just really want to think what to do next regarding T4/T3 replacement.

Sorry for yet another exceptionally long post, and thank you for reading.

26 Replies

Hi - sorry it is impossible to monitor treatment with t3 without an ft3 result. On any form of t3 tsh will be very low and ft4 will also typically lower as the body doesn't hold what it doesn't need. So the next thing you really should do - before any dose adjustment - is to have your ft3 tested.

Having looked at last post, you also really need a re-test of your nutrients, vit d, vit b12, folate and ferritin. T3 will really emphasise any deficiencies in these and you don't have any recent figures.

You really need to know all the factors when taking t3 or else you are just taking a stab in the dark.



Thanks startagaingirl,

I will ask the endo to test FT3. He will ask why I want that tested, what do you think would be best to say to him to convince him to test it?

I got all the nutrients the GP would allow tested but I don't have the results yet. I shall ask endo to test any others GP wouldn't allow.


If an endo who is supervising treatment with t3 doesn't understand the need to test ft3 then he isn't much of an endo! Has he discussed your results with you? How has he described them? Suggest asking him how he is judging dosing without this. It really is the only way to monitor ft3 treatment.

Just re-read your post and your t3 dosing pattern concerns me - I hadn't noticed that previously. With that are you really managing to take it at least 2 hours after food (3 if meal had protein) and an hour before food with every dose? If not then you won't be absorbing as much as possible from it. It really isn't necessary to split the dose, especially once your system has adjusted to t3. I take mine in one dose at night.

Though your last change from 75/35 to 50/40 was actually a dose reduction - and that seems to coincide with the increase in symptoms, given that it does take a few weeks for the t4 level to decrease in the body. It could just be that.

It could also be that you are over-medicated at the minute - under and over symptoms are not clear-cut - or it could be that your increased t3 dose has used up some of your nutrients faster than you are providing them, hence leaving you no longer able to effectively use your t3 dose. It is impossible to tell accurately what is causing current issues without those tests.

Good luck



I get almost no time with the endo, he doesn't really discuss results with me, just asks how I'm doing, and I tell him well, and I ask to increase my T3 dose and he decides if he should also decrease my T4 at the same time based on my results. I only get to see him every 3 or so months, so I haven't seen him since this change in how I'm feeling, I'm seeing him on Thursday.

The Endo has recommended that is how I've to take it, he's big into dividing doses, I was going to ask him to divide less.

I know I don't have those tests, but I have to decide what I want to do on Thursday when I see him as I then won't get to see him again for another 3 months. I've no idea what to do if I should ask him to increase T3 and drop T4 or go back to where I was before the last change. The thing is the change also coincided with work changes and I just don't know what the cause is, I'm pretty sure it's the work thing, but I don't want to give up my job then find out I would have been okay if my thyroxine levels were different.


Yes well - if you are getting access to NHS t3 through him then maybe it is worth it. Otherwise I really don't think he is worth bothering with as he obviously knows very little about thyroid, as he has no results there that let him decide whether to adjust t4 or not.


Hi Kittenmittens,

I don't know a lot about levels etc as I'm still learning.

I mentioned about quitting your job. I'd been diagnosed for about 12 months and suffered with severe depression and exhaustion. Not knowing a lot at that point about underactive thyroid I blamed my job and got to the point were I dragged myself to work one day last November and walked out following a meeting. I was diagnosed with depression, my levels were checked and my thyroid was way out of sync. It took a while to get my levels back to normal. I went back to the same job in April, I feel great and I love my job.

Leaving my job generated finacialy difficulties which I am still recovering from. I thought my job was making me I'll. If I had have known then what I know now I would have done things very differently and been £10k better off. Please don't do what I did think about work carefully before you make any decision about your job. It was a very costly mistake for me.

I hope you get everything sorted soon

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HI I had quite good T4 readings although they were depleted as well. It was the production of T3 where I was sadly lacking. The offer of thyroxin for me at the time only addressed my T4 problems of which were hardly worth addressing at the time so Thyroxin had absolutely no affect on me at all. As for synthetic T3 its very expensive so good luck with getting your GP to agree with prescriptions this for you because even though my tests showed little to no production of T3 there was no way my GP was going to prescribe for me synthetic T3. I ended up seeing a private specialist who put me on Nature Thyroid (pig hormone) and I haven't looked back. Feel great now and according to my GP my thyroid is just fine. I said "Yeah that's because I am taking Adrenal support (which is also important) and 3 grains of natural pig hormone every day. He sent me to a NHS specialist who wasn't even willing to look at the private tests I had done and in fact has recorded no thyroid dysfunction. We are in the process of getting my private Endocrinologist to liase with her...Honestly the NHS Endocrinologists really need to waken up on how they are misdiagnosing people with thyroid malfunction they are truly awful. Right now according to my GP I do not have a problem which is absolutely disgusting. Were taking it further because we have to since without my thyroid pills I could potentially become very ill. I buy them and intend to keep buying them but I want it on my record that I do indeed have thyroid disease. So in answer I found Thyroxin didn't help me in the least. I further read it is very bad for the body.

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I tried Thyroxine and it seemed to make me ill, I have not tried T3 but am on NDT at the moment which does seem to be helping me. I have been to 2 endos and they have been no help at all. I am trying to work things out for myself now taking vitamins and minerals etc. I would consider asking the endo if he thinks NDT would be helpful for you.


Kittenmittens, the advice from Startagaingirl is really spot on as far as I can tell. I would say exactly the same:

- you must have an FT3 test to understand what is going on. If your endo won't, then go private.

- get your other bloods done, especially iron, b12 and vitD. These really must be in the upper quartile.

- books to read 'Stop the Thyroid Madness' and another one I can't remember but will come back to you.

I can't advise on T3/T4 meds, I've just been able to get T4 to work for me by getting by minerals up.

Do re-post with your FT3 results. It's the only way I'm afraid. Good luck, Anna.


Perhaps your pituitary is not responding properly (secondary hypothyroidism) as both your thyroid levels and TSH are low. So perhaps you need to ignore your TSH and increase your T4. Has your doctor mentioned secondary hypothyroidism to you? What sort of blood test results did you get on thyroxine alone? With your T3 and T4 levels my TSH would have been really high.


TSH and ft4 are both low because she is on t4 + t3 combo. That doesn't produce the same results as t4 only - she does not have secondary hypo or a pituitary problem.


I am also on T4 + T3 and generally have a TT3 of 2.4 also. But my t4 is much higher at around 15 and my TSH is also higher around 0.5. So I'm either overproducing TSH and over replaced or her pituitary is under producing TSH and she is under replaced (perhaps backed up by the extreme fatigue)? Or she is taking too much T3 and that is why the TSH is low?


There is no such thing as taking too much t3 as long as ft3 is within range. We are all individuals with individual requirements for ft3 levels. Results cannot be directly compared for different people. The fact that your tsh is higher would generally be interpreted to mean that you actually need a slightly higher in range level of ft3. It could also be that you are not using your ft3 effectively in your cells because of low nutrients. But the important thing is how do you feel?


You see I can't tell from your message are you hypothyroid or hyperthyroid.

Have you ever ver taken thyroxine?

Let me know


I have read your posts now. If you are taking vitamins be very careful what you take. I have a very busy life and sometimes fruit and veg can be the last thing on my mind -I do try to eat as much as I can. Well I bought a supplement containing fruit and veg and they made me really unwell they cost £50 for 60. I was so tired I would have slept every time I sat down then I felt just not right as if something was affecting my stomach so I stopped taking them at tea time and took them in the morning I had a suspicion then they were not agreeing with my hypothyroidism, I then thought it was better for a while taking them in the morning then I started getting palpitations and thought I was taking too much thyroxine then I started getting symptoms of hyperthyroidism still with palpitations so I telephoned the GP he told me to reduce the thyroxine for a few days well eventually I made myself really ill I felt disorientated fuzzy head and very very tired.. GP took a blood test and told me it was fine I honestly couldn't believe that. I did eventually wonder if it was the supplement so stopped it. It took ages for the effect of that supplement to leave me and took them to the chemist to get him to check what was in them and the result was they contained aloe Vera and calcium and broccoli - just to name a few - and they all affected hypothyroidism. I am fine now it has taken ages. My GP told me that all active ingredients affect the condition and I never take anything now without checking first. If you get palpitations you know there is something wrong with your dosage you are taking. My GP told me both conditions can give you palpitations and that is very unsettling..

Let me know how you are


Hello kittenmittens

I was diagnosed with hyperthyroidism (high) and after radioactive treatment I got hypothyroidism (low). After all if the t3 and t4 intakes and the right level of dosage, I was still feeling very weak, sad, tiere, sleepy, fatigue and don't want to do anything even though I have a very good job as a computer engineer, I did not want to work. Life was very boring until........ I started anti depressant since it was the number one reason I felt all of these symptoms. Since hypothyroidism causes depression, you must than start antidepressants such as Prozac 20mg or something similar.

I have been on it for the last 3 years and feel great about life and work. There are ups and down but feel superganic. Continue your thyroxine medicine because you would have to have these hormones. Good luck and best wishes


No it is absolutely not necessary to start anti-depressants because of hypo - simply get all results (including nutrients) optimal and in the vast majority of cases the depression will go away.

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Goodness sounds like you've been through the mill with this one!! It amazes me that supposed specialist Endos are so useless frankly. Of course you can't fix your t3 if you don't know what your levels are....isn't this blindingly obvious? So frustrating for you! I have a private Endo who luckily actually understand his stuff and he explained to me that there is a recognised sub group of hypothyroid (usually hashimoto's) sufferers who don't convert t4 into t3 without having extra t3 present, if that makes sense. So basically it doesn't matter how much t4 you take your body will never get any benefit from it because it can't convert it into t3. However when you add in some t3 your body then somehow manages to remember how to convert it and you will start to get the added benefit. So you need both. And the relationship between them is important. I think you have always been on an extremely low t4 dose anyway, reducing it to 50mg basically renders it useless. You need to up both at the same time until you level out. I am currently on 200mg t4 with 25mg t3 which works for me. I agree with what someone else said above, you only need to take it in 1 dose. There's no evidence at all that split doses make any difference so don't muck around with that. Take it at night. Your body accepts it better overnight apparently. Don't combine with any other meds at all for 4 hours, you probably know that. And take a good multivitamin loaded with vit b & d coz very typical to be low in these too. Final piece of advice....get a new Endo?!! Hope that helps, good luck, Abi x


I am still baffled by how so many of you get prescribed T3? My GP was angry when I mentioned it.. like 'you think you are clever'?


Hi there,

Do you have an under active thyroid?

I take levo every day as I had my thyroid removed. I have heard great things about t3 but never been offered it. I'm under an oncologist as I had thy cancer and had my thyroid removed so my tsh levels need to be monitored. I don't really seem to get a say in how I feel, as I have to be on a certain level to keep my th suppressed. I have had many side effects and definitely when your mess change it can cause changes. Sometimes it takes up to three months to see a difference. I would say if your job is stressful this would defo be contributing, sounds like it may be a combination of things. Could also be adrenal fatigue. Maybe it's like s vicious circle of stress and worry and fatigue. When I feel like this I do guided meditations and it normally helps. Hope you get it sorted out!!


Hi Kittenmittens, 'Your Thyroid and how to keep it healthy' by Dr Barry Durante-Peatfield is the other book that explains everything. Your Endo does sound particularly rubbish. A good Dr in Ecological medicine would help. There's one in Bristol called Dr Rohrbeck, search for others. Good luck. Anna

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Yes - agree! Brilliant book.


For me, personally, I found I was gluten intolerant at the same time I started thyroid treatment. Gluten intolerance and thyroid problems tend to go hand in hand, so perhaps that's something you might want to consider. :)


Hi I have been contacted by someone that has asked me to help. I have read your latest post and there is something that hasn't been mentioned, your adrenals. In my opinion an Adrenal Stress Test (saliva) is the first point of call with any treatment concerning a low metabolism. If you take thyroid hormone with low adrenal reserve then you will crash the body, not only that thyroid hormone will not be taken up adequately in the cells which is essential for a good metabolism.

Being guided by blood tests isn't successful as you are only measuring the messages from the pituitary with the TSH and blood levels with the FT3 and FT4 tests. Thyroid hormone has to be taken up in the T3 receptor sites, basal resting pulse and a symptom check are essential here

As for how to take thyroid hormone only one dose per day of T3 and T4 if you take both, by trickling in the thyroid hormone you are not "waking up" the receptor sites which is essential I would never advise anyone to take T4 only as you have no way of knowing how much is being converted and entering the cell only symptoms, pulse before rising and body temperature will tell you this.

Again the adrenals are key here and a test I would say essential. My book will be published in the not too distant future and I hope it's publication will explain how these tests are failing.


Try taking your T4 before going to bed not in the morning. T3 is fast acting but gives you lots of peaks and troughs as the medication is short lived in the system. A bit of T4 will help stabilise. That was my advice from my endo. I was on T3 only. I have no natural thyroid function. Better and more natural for the body to be on a combination apparently. So I take 40mg T3 75mg T4.

Hope you can get sorted and feel better soon.


Thank you everyone for your replies, I will get back to you and let you know what's going on, etc, but at the moment I need to sleep, I will get back on when I get a chance.


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