Low TSH, normal T4 and T3: Hi, I'm hoping someone... - Thyroid UK

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Low TSH, normal T4 and T3

hanflow profile image

Hi, I'm hoping someone can offer some insight, please. Excuse the long story but not sure if it is helpful context. Also, I'm a bit of a dunce when it comes to my thyroid so please excuse me if the answer to this is wildly obvious!

I have MS and about 6 years ago I had a treatment that recorded thyroid disease as a potential side effect. A couple of years after finishing the treatment I was 7 weeks pregnant with my first baby and due to my thyroid levels which were done via a routine blood test, I was told that I likely had Graves Disease. By the time I was seen by an endocrinologist I had switched from hyper to hypo so started on levothryoxine which I continued to take for 2 years. When I fell pregnant with my second baby, I went back to being hyper but at quite an extreme level. I started on carbimozale and have been taking that for the past 18 months. It has fluctuated a little and I've moved between 10mcg to 20 mcg a day a couple of times during that time. However, every month for the past 4 months, I've gone between the two, i.e. one month at 20, the next at 10, then back up to 20.

Fast forward to now (currently on 10mcg a day) and I had my bloods done yesterday by my GP as I've not been feeling well (fatigue, hunger, general fuzzy head) and they've come back with a TSH of 0.02, T4 of 10.2 and T3 of 3.8. I'm assuming that this means that my medication is too low but can anyone offer any insight of what may be triggering such a fluctuation? It all seems quite suddenly 'off'. I'm not under a consultant at the moment and we've just moved to a new area so I'm struggling to get any professional advice.

Thanks so much in advance

32 Replies
SeasideSusie profile image


Have you ever had the following thyroid antibody tests to definitely confirm Graves disease:

Thyroid Stimulating Immunoglobulin (TSI) or

TSH Receptor Antibodies (TRAb)

Or have you ever had Thyroid Peroxidase (TPO) or Thyroglobulin (Tg) antibodies tested?

hanflow profile image
hanflow in reply to SeasideSusie

Hiya, I have an antibodies test about 10 months ago, just after I had my second child. It was the only time I've spoken to an endocrinologist consultant who said they would repeat the tests in a year to see whether there was any change. If there wasn't, they would diagnose me. Does that sound about right?

SeasideSusie profile image
SeasideSusieAdministrator in reply to hanflow

We need to know which antibodies were tested.Only TSI or TRAb confirm Graves.

hanflow profile image
hanflow in reply to SeasideSusie

Right, okay. I'm not sure. I'll just speak to my GP again.

hanflow profile image
hanflow in reply to SeasideSusie

thanks for the reply, by the way

Can you post up which tests, what the result was and the reference range?

hanflow profile image
hanflow in reply to Star13

The ones I've had are the ones in the post. I haven't got results for anything else. I've gone with a reference range on google but I'll ask my GP which one they are using.

The reason folks are asking for antibody tests are is that hypothyroidism often starts with a phase where the TSH T4 and T3 results mimic hyperthyroidism Graves. The only way to tell what you have is by antibodies. We have had folks on here misdiagnosed. The treatments are totally different.

hanflow profile image
hanflow in reply to Lalatoot

Thank you. I've requested a copy of the TSH receptor antibody measurement test so hopefully that will provide some insight.

Your first option to try and find out what is really going with your thyroid is to ask your surgery and hospital for copies of all your blood test from before the problem started up to now. You are entitled to copies of your blood tests. Just say it’s for your records

Once you have them add them to this post and the clever people on here will be able to work out what tests were missing that you need to have done and comment on the results of those you have done. They will need the reference ranges as they vary from lab to lab

hanflow profile image
hanflow in reply to CaroleM-A

Thank you. I've requested a copy of the TSH receptor antibody measurement test so hopefully that will provide some insight.

Hello Hanflow :

Just to add when taking an anti thyroid drug it blocks your own thyroid hormone production.

Your thyroid hormones will stop rising and given a little time your T3 and T4 high levels start to fall back down into range and your symptoms relieved.

If your immune system response is still active and driving your levels up this is something of a holding pattern, waiting for this phase of the disease to pass.

To some degree, you have been put " on hold " , with the endocrinologist having the control stick.

I liken it to a plane waiting to land and being put on automatic pilot while we wait for a slot to land and return to manual - while we wait for this attack from your immune system on your thyroid to stop.

It takes considerable skill and knowledge on the part of the endocrinologist to get you on the best level of AT drug for you, and it can take several very small titrations in the AT drug over a relatively short or long period of time, as this auto immune disease runs it's own course.

I think this last blood test result shows your levels too low for you and likely you are now experiencing symptoms of hypothyroidism and likely a lower dose of the AT drug might well be considered, if your antibodies have droped down and the attack on your thyroid passed.

Some endocrinolgists add back into the prescription T4 along side the AT drug so the patients T3 and T4 don't fall too low giving symptoms of hypothyroidism.

So, we do need to see which antibodies were over range and positive at diagnosis and the medical evidence needed for this treatment course, and if you also find your TSH, T3 and T4 results and ranges at diagnosis, before starting the AT medication this is also useful for forum members to see,

P.S. you are not a dunce - we all have to start somewhere.

Knowledge is power, and the knowledge will be shared with you through this forum and Thyroid Uk the charity who support this patient to patient forum, and we have all been there, in one way or another.

I'm with Graves diagnosed at 56 and had RAI thyroid ablation the following year and knew nothing about anything until around 10 years later.

Thankfully I found this forum and started my own thyroid journey back to better health. I now mange lingering Graves, thyroid eye disease - caused by the RAI - and hypothyroidism and am having to self medicate as I was unable to access full spectrum thyroid hormone replacement through the NHS in 2018.

hanflow profile image
hanflow in reply to pennyannie

Hi, just to say, I've posted a bit further down but wanted to say thanks for your message and such a detailed response. Also for sharing your own experience, I do really appreciate it.

SlowDragon profile image

TSH of 0.02

T4 of 10.2

T3 of 3.8

Please add ranges on these results (figures in brackets after each result)

Ft4 and ft3 look very low, suggesting you are now hypothyroid

TSH is obviously suppressed, but can be extremely slow to respond to changes in thyroid levels

You need TSI or Trab antibodies tested for Graves’ disease

TPO and TG antibodies tested for Hashimoto’s/Ord’s disease

All thyroid tests should be done as early as possible in morning before eating or drinking anything other than water

Essential to regularly retest vitamin D, folate, ferritin and B12

What vitamin supplements are you currently taking

With MS presumably you supplement vitamin D

hanflow profile image
hanflow in reply to SlowDragon

Thanks. I do supplement with a relatively high dose of Vit D but not anything else. I'll have a look into the others. I have had very regular blood test, full blood count as part of my MS follow up so I'll look at the others you mention and see what they have typically been

SlowDragon profile image
SlowDragonAdministrator in reply to hanflow

Vitamin D should be tested twice year

Folate, ferritin and B12 annually minimum


Welcome to our forum.

Pregnancy brings about large immune-system changes to the body and so a time when during the hormonal flux, conditions we may have been carrying/predisposed to are suddenly exposed.

You mention TSH-Receptor antibody tests (TRAb). These indicate Graves but there are TSAb (stimulating variant of the TRAb that can send TSH low & thyroid hormones sky high) and TBAb (blocking variant of TRAb that can present like hypothyroidism with high TSH & low thyroid hormones).

It is usual to switch between the two and without tests confirming exactly which antibodies are present, difficult to provide & plan for whole treatment because when in remission it is impossible to tell if its due to reduced ‘stimulating’ AB’s, or the elevated ‘blocking’ AB’s that are cancelling out elevated ‘stimulating.’ When this happens you can have falsely good TSH & thyroid hormone lab results but feel extremely unwell.

Also thrown into the mix are Hashimotos antibodies that are commonly associated with Graves too. These AB’s destroy the thyroid gland and again goes through stages of high hormone release and low hormone levels that incite hypothyroidism.

This is why it is essential to have all antibodies checked and something the NHS is not always willing to do. This is when members use private labs & post results for others to comment.

It must be difficult looking after two young children with all this going on. I would ask for a referral to an endocrinologist because your GP will have little understanding of the antibody implications. Meanwhile post whatever results you have complete with ranges (numbers in brackets) for members to comment.



hanflow profile image
hanflow in reply to radd

Thanks for your kind message. I've posted a message below. I've asked to speak to the consultant that I spoke to last year in advance of being transferred to a hospital that is closer to where we now live. Thank you

Thanks all for your input, much appreciated. I had this response this morning...

"I can see a positive TSH receptor antibodies in May 2021 – 9.8 IU/L. None in November.

Basing from this result, you will require a definitive form of treatment like radioactive iodine.

Carbimazole just controls the excess thyroid hormone but will not cure you.


They've reduced my Carbimazole to 5mcg a day so hopefully that will help in the short term. I've asked what antibodies were tested, what the results were and the normal range so hopefully I will get feedback soon. Thanks for the prompts everyone, I really do appreciate it. I've also asked whether there is an indicative diagnosis as this is the first that I've heard about these bloods results and they were taken in May!

PurpleNails profile image
PurpleNails in reply to hanflow

TSH receptor antibodies (TRab) if positive is considered evidence of Graves. Did it include a reference range usually seen as (0-1) or <1 for example.

5mg is viewed by medics as lowest possible dose as it’s the smallest dose manufactured but it’s possible to lower further, If needed, by taking alternate days or splitting a tablet. What were you taking before?

Your FT4 & FT3 current look very low. Doctors seem unbothered by this as they focus on getting an in range TSH. But you could feel unwell unless dose adjusted to keep you in range. How frequently are you tested, especially after dose adjustment.

TSH can remain low. I’ve been taking carbimazole over 2 years my TSH has never risen into range.

hanflow profile image
hanflow in reply to PurpleNails

Thank you. That’s helpful.

Just had a response from the endocrine nurse who said...

“TSH receptor antibodies 9.8 IU/L (normal range 0.0-0.9). The TSH receptor antibodies result likely indicates Graves’ thyrotoxicosis.

However, latest TRAbs is an improved level in comparison to December 2017 when your TSH receptor antibodies was 40.6 IU/L”

So, I assume that’s it?

I feel grateful to at least know what it is although I was happily ignorant for a good while! 😬 I just really hate the idea of the radioactive iodine treatment and not being able to see my kids for a while.

Thanks for sharing your experience and insight and to everyone else

PurpleNails profile image
PurpleNails in reply to hanflow

I’m hyper from a toxic nodule (I don’t have autoimmune) So I was told RAI was my treatment plan almost straight away because is doesn’t have the potential of remission, unlike Graves. I wasn’t ready to proceed so haven’t consented to treatment. I still take carbimazole. I will either take it life long or until a complication arises and I will need to have either RAI or surgery. It’s implied we don’t have a option but ultimately we can decide on our own treatment.

5mg is a very low dose, you may find if you give it longer you will remain In remission and can stop the medication, it might just take longer than the doctors guide. The TRAb lowering is a very good sign the treatment is working.

I made the decision to delay because RAI isn’t reversible, but don’t let me sway you If you feel fully informed & decide it’s the right treatment for you. I just wanted to make sure you know you have options.

hanflow profile image
hanflow in reply to PurpleNails

So helpful, thank you. I didn’t research my MS treatment enough and ended up with the thyroid issue so I’m keen not to repeat that! I’m definitely not informed so that is really helpful, thanks again

PurpleNails profile image
PurpleNails in reply to hanflow

What has the doctor explained to you?

Unfortunately I have found doctors prefer to dish out leaflets, whilst refusing to actually discuss any queries I wish to raise.

I’ve now been sent a collection of 4 ‘out of date’ versions on RAI treatment. Here’s a link to the leaflet hospitals often have.


The information is presented how a doctors might promote the treatment ie they are factual & lightly touch on the negatives. So it worth familiarising yourself with how medics view the treatment.

Link to other leaflets.


hanflow profile image
hanflow in reply to PurpleNails

Nothing explained as yet. The first I've been told about the antibody results was in an email today after I chased it. I've asked to speak to the consultant but I feel like I can go into that knowing that I do have options. At this stage RAI isn't feeling like the best option for me. Thank you and sorry that you didn't get the information that you should have.

tattybogle profile image
tattybogle in reply to hanflow

don't assume you have to have radioactive iodine ablation . (or surgery to remove thyroid) just because TRab have confirmed Graves.It IS possible to stay on low dose carbimazole (or the other one ~ PTU) for many years/indefinitely .... and remission from Graves becomes more likely the longer you stay on antithyroid drugs. (There was a study posted on here awhile ago with remission being found after up to 5/7 ish? yrs on carbimazole, )

The risk of an adverse reaction in the liver to carbimazole /PTU do not increase the longer you are on it... so if your liver is OK on it now, then you are in no more danger of it affecting your liver by staying on it for longer.

They won't tell you this though... because it is more (cost) effective for NHS to get you off the antithyroid drugs and onto Levothyroxine permanently.

On Levo they only have to give you one TSH test a year, and about £12 worth of Levo.

RAI is very efficient in this sense.. much cheaper than the frequent on-going thyroid blood tests needed to monitor carbimazole. .. and no ongoing Endo involvement at all once on Levo.....so it is promoted as the 'preferred' option according to the guidelines. (and it's simpler/cheaper than surgery).

So, do LOTS of research about your options , ask lots of questions on here~ there are some who are happy with RAI ~some who had no choice cos their fT4/3 results would not come down enough or stay stable enough on carbmoazole /PTU. (or they had a reaction to them) ~ some who deeply regret it and with hindsight would have had surgery instead if they'd been given the option ~ and some who wish they had stayed on long term carbimazole /PTU.. but were not informed it is an option.

Many are rushed into RAI. we see it all the time on here.. people being told at their first appointment with endocrinology that they will be having RAI if they are not in remission after 18 months on carbimazole etc.

Your positive TRab do not mean you have to have RAI unless you want to.. and they have lowered significantly already.

This healthunlocked.com/thyroidu... post contains a link to a very enlightening article by an endocrinologist (who was also the Queen's physician in Scotland) called "a counterblast to guidelines" (it's about half way down the replies)

a counterbalst to guidelines Prof A Toft

"" I am so concerned about the state of advice on the management of primary hypothyroidism that I am increasingly reluctant to suggest ablative therapy with 1-31 or surgery in patients with Grave's disesase irrespective of age or number of recurrencies of hyperthyroidism " .

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

helvella profile image
helvellaAdministrator in reply to tattybogle

The medical professions keep making logical errors.

On the one hand, presenting RAI as "the only" answer. On the other hand ramping up excitement about possible alternative treatments. There is unlikely to be any advantage to RAI patients from future options. There just might be for those who have stuck to anti-thyroid medication.

hanflow profile image
hanflow in reply to helvella

Thanks so much everyone. To be honest, I don’t really feel that I have any real symptoms or issues with my thyroid. It’s only really been the past 6 months that I’ve started to have some headaches and the fatigue but it’s not unmanageable and with two kids and being self employed, is probably not the only trigger! It’s therefore reassuring to hear that radiation isn’t the only option as I don’t have an issue with being on medication so long as I can have it reviewed regularly. I’m sure as time passes I’ll have a better idea of symptom spotting. I have epilepsy as well so I’m used to the idea of taking medication for life.

I sound like a very unhealthy person, just bad luck! I rarely get a cold though!

hanflow profile image
hanflow in reply to tattybogle

Very helpful, thank you!! Lots of reading to do which I will before I speak to a doctor. Thank you!

pennyannie profile image
pennyannie in reply to hanflow

Hey there - can I just add - there is no cure for an auto immune disease, it runs it's own course, and antibodies wax and wane which is why there were antibodies in May but not in November .

Carbimazole doesn't cure you, and nor will RAI cure you : we are looking at an auto immune disease that attacks the body.

Carbimazole can be used long term to control excess thyroid hormones, and that's the safest path to walk.

I'm with Graves and post RAI thyroid ablation in 2005 and now manage lingering Graves, thyroid eye disease and hypothyroidism and am now self medicating as I am unable to access full spectrum thyroid hormone on the NHS.

Hopefully with this reduction in the AT drug your T3 and T4 numbers will increase and you will start to feel a little better :

I read of people having to cut their AT medication into quarters and halves and staying on AT medication for many years adjusting their dose to their life " stressors ".

The RAI is a toxic substance that will burn out your thyroid is situ, ultimately rendering you hypothyroid and needing to take T4 - Levothyroxine which you have already been taking for hypothyroidism anyway.

So, all this RAI treatment will do is eradicate your thyroid completely and believe me, your thyroid is so much more than you'll ever be told.

The thyroid is a major gland responsible for full body synchronisation including your physical, mental, emotional, psychological and spiritual wellbeing, your inner central heating system and your metabolism.

Currently there are basically 3 thyroid hormone replacement treatment options available.

Currently, routinely, the NHS only offers 1 :

I now self medicate as T4 Levothyroxine - seemed to stop working for me :

I have tried all options of thyroid hormone replacement and nothing replaces the human gland - all medicines can have side effects and please fully research Radio Active Iodine.

You might like to dip into the Elaine Moore Graves Disease Foundation website for more information - or just now check out the section on RAI as I'm sure you are with information overload.

hanflow profile image
hanflow in reply to pennyannie

thank you so much for this. I'm ever so grateful that you spent the time to write this and share your experience. I will absolutely fully research it but at this stage RAI isn't feeling like my best or preferred option.

Hi. I have Graves. I have been diagnosed 12 months. I am on the alternative to Carbimazole PTU. This site has been amazing. I have decided to stay on anti thyroid drugs. New Zealand only prescribe T4. No T3 or NDT. I will not consider RAI. I get pressured into making an ultimate decision all the time. Do what feels right for u. Only if my liver or kidneys or heart cannot cope will I make a big decision. It’s your body and your choice.

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