I normally post on the AF forum and as some of you may be aware, there is a link between thyroid issues and AF. Since 2004, blood tests have indicated that I have an overactive thyroid. TSH low at 0.02 mu/L; T4 just normal at 20.8 pmol/L and T3 just high at 5.9 pmol/L . Yesterday, I saw an Endocrinologist who who talk about a goitre and he has prescribed a daily dose of 5mg carbimazole. He is seeing me again in three months time and if the thyroid has responded to the medication, he said he will arrange for me to have radioiodine treatment to stabilise thyroid levels. Apart from occasionally getting hoarse and (according to my wife) mood swings 🥴 I am not aware of any symptoms. This is all new to me therefore I would appreciate any thoughts you may have about this treatment.....many thanks.
Overactive thyroid......: I normally post on the... - Thyroid UK
Overactive thyroid......
Flapjack
TSH low at 0.02 mu/L; T4 just normal at 20.8 pmol/L and T3 just high at 5.9 pmol/L
What are the reference ranges for these? If FT4 is "just normal" that suggest's that it's not over range. This isn't necessarily overactive thyroid and carbimazole isn't necessarily the treatment you need. And Radioiodine treatment is a massive step, probably unnecessary.
However, before you know exactly what condition you have, and before any treatment, you really should have a full thyroid panel to include
TSH
FT4
FT3
Thyroid Peroxidase (TPO) antibodies and Thyroglobulin (Tg) antibodies which would confirm autoimmune thyroid disease Hashimoto's (underactive) which causes fluctuations in test results and swings from hyper to hypo
Thyroid stimulating immunoglobulin (TSI) and Thyroid stimulating hormone receptor antibody (TRAb) which are the tests for Graves disease which is the most common cause of overactive thyroid.
If you are positive for Hashi's then carbimazole and RAI are definitely the wrong treatment so you should run away from this endo as fast as possible.
Do you actually have a goitre?
Thank you SS for such a comprehensive response. TSH range is 0.35 - 5.0; T4 is 9.0 - 22.0 and T3 is 2.3 - 5.1. A week before the next appointment I am to have blood tests for TSH Receptor Ab; Thyroid Function Tests; Free T3 and Thyroid Peroxidase Ab. I assumed I had been put on a low dose of carbimazole (5mg) to see how this would impact on current readings. He held my neck from the rear and asked me to swallow and said there were signs of a goitre but it was not easy to understand everything that was said. Fortunately my wife was with me. I think he was just trying to make me aware of what might happen subject to the outcome of these further tests in November. I hope I’ve made sense but my knowledge of AF is certainly better than issues with the thyroid (so far!). Thanks again.
A week before the next appointment I am to have blood tests for TSH Receptor Ab; Thyroid Function Tests; Free T3 and Thyroid Peroxidase Ab
In that case I think it was premature to put you on carbimazole. Most endos are diabetes specialists with little knowledge of the thyroid. We hear of many cases where overactive thyroid has been diagnosed and treated when in fact, once thyroid antibodies have been tested, it has been nothing of the sort, it has been Hashimoto's (underactive)
TSH: 0.02 mu/L (0.35 - 5.0)
FT4: 20.8 pmol/L (9.0 - 22.0)
FT3: 5.9 (2.3 - 5.1)
Even though your FT3 is over range, I don't believe this is overactive, your FT4 would be much higher. I can't understand why you have been given this diagnosis and started on carbimazole without confirmation from antibody testing - but yes of course I can, your endo doesn't understand enough about thyroid disease.
Obviously that is concerning. As far a you know, can the dose of carbimazole do any harm?
As mentioned in other replies, treatment for overactive thyroid will lower production of thyroid hormones, so giving you carbimazole will lower your FT4 which in turn will lower your FT3 as T4 converts to T3. But your FT4 is not over range.
Do you actually have any symptoms of over active thyroid:
thyroiduk.org/tuk/about_the...
If not then I would question why you have been given carbimazole.
Symptoms include palpitations, mood swings, anxiety and apparently, after feeling my neck and asking me to swallow, a goitre. I am assuming that is what prompted the Consultant to prescribe carbimazole. As suggested by ling, I am hoping the Nov tests will clarify my condition but in the meantime, could taking 5mg carbimazole cause any harm if ultimately it is decided my thyroid is “OK”.
Symptoms include palpitations, mood swings, anxiety
As well as being symptoms of overactive thyroid, those are all also symptoms of underactive thyroid.
after feeling my neck and asking me to swallow, a goitre.
You can have a goitre with an underactive or overactive thyroid.
I'm not saying you have an underactive thyroid, your test results don't show that, but neither do they show you have an overactive thyroid. You have a below range TSH, an in range FT4 and a slightly above range FT3, these may be your normal levels, if you've never had your thyroid tested before who's to say they're not normal for you. So you can see why there is some doubt over your "diagnosis".
As suggested by ling, I am hoping the Nov tests will clarify my condition but in the meantime, could taking 5mg carbimazole cause any harm if ultimately it is decided my thyroid is “OK”.
I cannot tell you if carbimazole will cause any harm if you don't have an overactive thyroid. I can only look at it from a layman's perspective and what I would want to do in your position. Carbimazole can have side effects so you should read the whole of the patient information leaflet carefully. I wouldn't want to take a medicine that I don't know whether I really need and risk any of the side effects.
And as already pointed out, taking carbimazole will lower your production of thyroid hormones. With your FT4 not even over range, it will most likely lower, by how much nobody can tell you, and depending on how low it goes you may get symptoms of hypothyroidism.
I certainly would not want to wait another 3 months for further tests to know if I have the condition which I have been taking medicine for, I'd want to know if I have the condition before I start taking it.
I understand the point you are making but we are where we are and we have a NHS system which, whilst far from perfect, tries to do the best it can under extremely difficult circumstances. This is not an excuse, it’s a statement of fact. As I see it, my (new) GP reacted in much the same way as the people here responded until I made him aware of my (controlled) AF condition. He referred me to a Consultant specialist who had a 15 year history of my TSH and T4 results but T3 for this year only. He asked questions relating to all the symptoms featured in the document you kindly sent me. He explained that I needed further blood tests a week before I saw him in November and that the medication he prescribed would help in that analysis, I assume by the effect it had on the blood tests. He explained the possible side effects and how I should deal with the more serious ones should they occur. All this has happened since May this year so from my perspective, the NHS responded well. Of course a lot depends on the final outcome, but I feel I have no option but to follow the advice given by the hospital and keep my fingers crossed for a successful result.
I am grateful for your and everybody’s advice because it has made me aware of things I need to clarify before more radical treatment is considered or pursued. Many thanks.......
1. Curious. Has your FT4 and TSH always been like the one you listed in your post?
2. When carbimazole pushed my FT4 below range, I experienced rather bad palpitations. You should watch out for that, and also if it triggers any AF.
3. Thyroid eye disease(TED). I don't know if you have any problems with your eyes, but watch out for this. Becoming hypothyroid from the carbimazole can trigger or make worse TED.
Positive thyroid antibodies levels also mean you are at higher risk of developing TED.
The Nov tests will be very useful in ruling out what you do not have, and what you potentially might be at risk of developing if antibodies levels are positive. Whatever thyroid condition your mom had, already increases your risk of developing something thyroid related as u already know.
Best wishes.
From 2004 until 2010 TSH was 0.05 then from 2012 to 2014 it was 0.01. No tests until 2019 when it was 0.02. For the same period, F4 has varied between 17.5 (2013) and 20.9 (back in 2006). Last test in 2019 it was 20.8. Range is 9.0 to 22.0 pmol/L. No thyroid medication.
Not aware of TED and it wasn’t mentioned at the appointment. It was palpitations which caused the blood tests to be taken earlier this year. The carbimazole leaflet says that the normal daily dose is significantly higher than the 5mg I have been prescribed so hoping that any effects will be minimal until tests in November.....thanks again for your help.
Saying that radioiodine treatment 'stabilises thyroid levels' is underplaying and even misrepresenting what can be the outcome. As the British Thyroid Foundation says, A common longer term side-effect of radioactive iodine treatment is an under-active thyroid gland (hypothyroidism). Even the NHS says Radioiodine treatment is where radiation is used to damage your thyroid, reducing the amount of hormones it can produce...... Treatment for an overactive thyroid often results in hormone levels that are too low – known as an underactive thyroid (hypothyroidism).An underactive thyroid is sometimes only temporary, but often it's permanent and requires long-term treatment with thyroid hormone medication.
You need therefore, to be absolutely sure that you actually do have an overactive thyroid before you consider undergoing that treatment, and likewise, that carbimazole is the right drug - it isn't unknown that medics mistake someone with autoimmune hypothyroidism for someone who is hyperthyroid.
Thank you Maisie, please read my reply to SeasideSusie. I’m sure he was only indicating what might be required subject to the outcome of further tests but I appreciate your point about the need for caution. Fortunately I am seeing the EP who performed my ablation just before seeing the endo....thanks again
I should have said that “stabilising” was not a term used by the doctor, it was my interpretation of what was implied.
Your results don't really suggest true hyperthyroidism to me, even without the reference ranges. People who are truly hyperthyroid would have a lower TSH and a substantially higher Free T4 and Free T3 than yours - say, very roughly, around 40+ for Free T4, and 10+ for Free T3.
In true hyperthyroidism the treatment is carbimazole or some other anti-thyroid drug. It cuts down the over-production of thyroid hormones from the thyroid. Given time and the appropriate treatment the patient may go into remission. Some people may never go into remission and have to have their thyroid nuked with radioactivity treatment, or may need their thyroid removed.
There is a condition called Hashimoto's Thyroiditis, also known to UK doctors as autoimmune hypothyroidism, which starts with a period of apparent hyperthyroidism, but eventually leaves the patient permanently hypothyroid.
In Hashimoto's Thyroiditis (known to patients as Hashi's) the problem is not over-production of thyroid hormones, it is the destruction of cells in the thyroid by the immune system that causes the problem. Damaged and dead thyroid cells release thyroid hormones into the body and bloodstream which can be detected by blood tests. Eventually, as a result of the damage caused by the immune system, the thyroid cannot produce enough thyroid hormones and the patient becomes permanently hypothyroid.
Some unlucky people have both kinds of thyroid problem - immune attacks on the thyroid and over-production of thyroid hormones by the undamaged parts of the thyroid.
Heart problems can occur with both hyperthyroidism and hypothyroidism. Palpitations and ectopic heartbeats are common, for example.
One effect of both hypothyroidism and hyperthyroidism is low nutrient levels. One effect of low iron, for example, is palpitations and tachycardia (fast heart rate). Palpitations may occur with low Vitamin B12 and low folate.
Low vitamin D is bad for the heart too :
hopkinsmedicine.org/heart_v...
If you haven't had any nutrient testing done in the last year then it would be a good idea to ask your doctor to test your iron, ferritin (iron stores), vitamin B12, folate and vitamin D. All these nutrients have effects on thyroid health and how well the body uses thyroid hormones. Doctors are not trained in nutrition and have no concept of levels being optimal or not. If you get your levels tested ask for a copy of your results including the reference ranges. The situation you need to avoid is being told that your levels are "normal" even if they are low in range. The aim for us should always be to optimise nutrient levels - and low in range is never optimal for nutrients. Most of us end up optimising our own nutrients with supplements bought online.
I had assumed you had diagnosed Graves.
Did your endo say what was the cause of your hyperthyroidism?
To diagnose Graves, TRAb or TSI antibodies must be tested.
To diagnose Hashimoto's, TPO and TG antibodies are to be tested.
Hyperthyroidism can also be caused by active nodules in your thyroid. Diagnosed via blood tests and a scan.
Thank you humanbean, I appreciate your comments. Clearly there is a lot to be considered but hopefully the route forward will be clearer once I have had the additional tests. What you said is interesting because my GP initially was not going to refer me, it was only because of the AF dimension.
cks.nice.org.uk/hyperthyroi...
Nice CKS mentions T3 toxicosis... see section on interpreting blood results in hyperthyroidism. May be useful for you!
Thank you, fairly steep learning curve methinks.
Very important to test vitamin D, folate, B12 and ferritin too
With autoimmune overactive (Graves disease) or hypothyroidism (Hashimoto's) low vitamin levels are extremely common
Request GP test these, getting these optimal can help improve symptoms
Like others say, BEWARE! My friends 21 year old daughter had radioiodine and her system is now wrecked
The hospital did not do well with her at all. My friends an ex midwife/nurse and is angry beyond words.
5mg day is a low dose of carbimazole. There are always risks, even with a low dose, but some people here are taking that much daily for the long term in preference to RAI.
Sometimes we aren’t aware of our symptoms. When I was first diagnosed as hyper, my GP said my heart rate was thumping away well beyond a normal rate, and couldn’t believe I wasn’t aware of this. It seems it had been going on for a while, and I had just got used to it.
It’s easy to say don’t go near RAI, and that with FT3 barely over the range that you don’t need treatment (other than the small dose of carbimazole prescribed). In your case, the AF makes it a less straightforward decision than usual. As well as discussing this with your endo, why don’t you talk to your cardiologist, and get them to explain why your endo is recommending a definitive approach, and whether they think it’s necessary.
Thank you for your very helpful reply. I think the endo is being cautious and only mentioned RAI as an option should the need arise. The EP (Cardiologist) who carried out both of my ablations is also aware and he suggested seeing an Endo. Fortunately, I have an appointment to see him just before I next see the Endo and hopefully, I should have the blood test results by then. Thanks again......
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