I have been on the same dose of Liothyronine for over a year now (50mg)
Results - T3 - 4.4 (range 2.4 - 6.0)
T4 - <5.4 (range9.0-19.1)
TSH- 0.01 (range 0.35-4.94)
Twice this month, my heart rate shot up to 210 bpm, tight chest and feeling faint.
I ended up in A&E the second time round. Dr's suggestion was my TSH was too low and with my thyroid results are not healthy, sometimes with the thyroid, these symptoms can be cumulative.
Has anyone else experienced these symptoms, after having been on the same dose of meds for around a year?
Any advice most welcome!
Maybe I need to change meds 'again' and bring T4 back into the equation?!
x
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Angie33
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Yes is the answer to your basic question ‘ do you suddenly get high HR though on same thyroid hormone dosing?’ But I can put mine down, 99%, to having Long Covid, a complicated syndrome that I have had things ruled out re. heart and lungs. The only diagnosis I have is ‘postural hypotension’ despite the fact my BP resting can be high, and with the slightest movement / domestic task my HR goes up to 135 +…so not as high as yours. My HR is supposed to go up to compensate for the hypotension; it was tested on a tilt table test when it went down to 61/40, and HR rising followed. But that doesn’t seem to explain how HR shoots up 30+ while seated just leaning forward to pick up a water glass on coffee table in front of me! The most disabilitating little task is standing at the stove trying to make a cheese sauce! Anyway within the process of trying to treat these cardiovascular problems over the last 4 years 9 months I have had ecgs, echocardiogram, 24 hour BP monitor etc…nothing seen abnormal, and just got put on, and left on 5-6 hypertensive drugs, while the tilt test specialist ( a Falls consultant in Geriatric dept) removed some of these believing these were causing the low BP/ high HR, and left me in my GP’s hands. His thought was that it was ‘over medication on Levothyroxine’ that was causing the high HR… my normal dose being 100 mcg levo.with a private endo. prescription of 15 mcg T3. But my TSH was stuck in the 0.01-0.02 level. Eventually got to see an NHS endo., who is interested in cardiovascular effects, 2 weeks ago who going through my 22 years of hypothyroid history ( showing overt hypothyroidism) said I needed the 100/15 combo, and that it wouldn’t be causing the high HR. Have you looked at other sites related to high HR…PoTS Uk, and my favourite Stopfainting.com run by a London cardio, Boon Lim? I tried a high mono T3 therapy as recommended by Dr Lowe for fibromyalgia, but it didn’t suit me as rose my blood sugar levels ( not good as also a diabetic), and think I probably need a higher dose of T3 than the 15 mcg to get FT3 above the 40s%…. Incidentally just in case you get put on a beta blocker to lower HR, Propanolol was specifically said to be able to reduce T3 serum by 20-30% according to my research. There are other reasons for high HR from low B12/ferritin, poor hydration, etc, but you’ll find them on the websites. Good luck.
Thank you so much for your help Judith. I really appreciate any advice. I have wondered if long covid plays a part or my low energy is still my under active 'abnormal' thyroid. My resting heart rate seems to be around 67-77. I think for being unfit (as no energy to work out these past few years) it's maybe an ok resting heart rate for being 58 yrs of age. I had had ecg's etc in the past as I ended up seeing a cardiologist. I was told everything was fine. I do have underlying ME (thankfully I managed to over come it, if that is what I had!! I think my body just crashed on me through being a class A personality, supposedly. I will look into the PoTS UK and stop fainting websites. Thank you!!! My B21 and ferritin seem fine when last tested 60 months ago. However, I am getting all my bloods tested again, privately, end of Jan next year. I do hope you are getting somewhere with your research! xx
I saw that class A personalities are more likely to get chronic fatigue etc! It’s difficult to unpick ailments and their symptoms ( I have diabetes, fibromyalgia, hypothyroidism and Long Covid)..tiredness could be any one etc. 60 months is a long time in terms of deteriorating vits/ mins levels, so good luck in 2025 in getting tests, and if necessary appropriate treatment.
Thanks Judith! My energy is in the gutter today after having reduced my T3 to 40mcg this week. As of today, I will be back on 50mcg and 25mcg of levothyroxine. It does scare me increasing my meds when I am having these heart and chest incidents but I agree with what everyone in this forum says. I find Greygoose very knowledgeable and very helpful in particular. I do hope start to improve next year too! xx
The medical name for the heart rate suddenly rising above 100 bpm is "tachycardia", and it has many flavours and causes, some of which are "normal" (e.g. exercise) but many are "abnormal". Finding the right cause can be obvious, or it could be complicated and take a long time, or it might not be found.
I developed tachycardia about 15 years ago, and in my case it was caused by severe iron deficiency and anaemia. I've also found that eating sugary stuff in large quantities can raise my heart rate well above 100.
I fixed my iron deficiency and anaemia myself which reduced the number of episodes of tachycardia I get, and I try to keep my sugar intake as low as possible (with varying success) but unfortunately, once triggered all those years ago it has become a permanent feature. I take a beta blocker (Bisoprolol) which helps. I started off at a low dose, but only took half a tablet when I needed it. Over time I had to raise the dose I took to taking a whole tablet every day.
Hi, thank you so much for explaining a lot more about "tachycardia". I was led to believe I was deficient in iron and anaemic, from my holistic GP. Whereas my NHS GP told me I was fine. Such conflicting advice eh I will read up on the link you kindly forwarded. Very interesting it is now a permanent feature after numerous incidents. I get roughly 2-3 a year xx
If you have the results of an iron panel, or can get one done privately, we can help you to interpret your iron and iron-related results, and whether or not you should be supplementing.
The biggest problem so many of us have with doctors - if I use a made up example ...
Suppose patients A, B and C get a Ferritin test which has a range of 13 - 150 and have results as follows :
A : 13 mcg/L i.e. bottom of range
B : 82 mcg/L i.e. mid-range
C : 150 mcg/L i.e. top of range
Many doctors would view all those results I've given as "normal" because they are all in range and they wouldn't prescribe supplements for Patient A.
But in reality, A will definitely feel the worst and B will probably feel the best. C probably won't feel much different from B, but high levels of ferritin are not a good idea long-term.
Personal anecdote :
I remember once pleading for a prescription for iron supplements when my ferritin was about 20. My doctor, very reluctantly and with a very pronounced scowl, printed a prescription for two months worth of iron and slammed it down on the desk in front of me. I took the prescription to my local pharmacy and, quite by accident, I learned from the pharmacist that prescription-strength iron pills could be bought without a prescription. I also found out on a thyroid forum that I could buy private tests online and use a finger-prick sample of blood. I have never discussed my iron with a doctor since. It is such a relief. In the end it took me nearly two years of supplementing at maximum dose to get my ferritin to mid-range, and then another five years of supplementing a maintenance dose for my serum iron to start rising. Those two months worth of iron I got prescribed by the doctor would have been like spitting in the sea. I no longer supplement, but I do test my iron once or twice a year.
To test an iron panel the one I use is the Medichecks one :
and, at time of writing, they are currently on sale with 25% off all their tests.
.
Oh, when I said I had tachycardia all the time, I didn't mean that I had it 24 hours a day. I just meant that, when untreated, I had bouts of it quite frequently, they could last quite a long time, and it could start at any time for no obvious reason. I'm doing quite well with my beta blockers., although obviously I would prefer not to need them.
Thank you so much!!!! I feel very low in energy and teary today with weakness. I guess I have reduced my T3 this week. It can feel a lonely frustrating journey at times when dealing with GP's and even my endocrinologist who states I need to reduce my T3 despite my T4 and TSH both being very low. It is scary stuff when it affects your blood flow and heart. I have ordered a thyroid test from medichecks. I will get the iron one too. Thank you so much for helping me. I feel people understand on this forum 😘😀👍
my endocrinologist who states I need to reduce my T3 despite my T4 and TSH both being very low.
I saw from your past posts that you had been diagnosed with Central Hypothyroidism (CH), which means that your pituitary isn't producing enough TSH for your needs and so your thyroid is not getting enough stimulation to make it produce all of your T4 and about 20% of your T3. This is why you need to take thyroid hormones. All forms of hypothyroidism, irrespective of the cause, are treated with thyroid hormones.
Doctors insistence on only testing TSH and treating based on that means that the NHS won't be able to diagnose CH at all, which is going to cause a lot of suffering. They defend this stupidity by saying that CH is very rare. But then if you never test for it, of course it is rare!
I diagnosed myself with CH (my pituitary is completely flat and doesn't work as well as it should). I couldn't tolerate Levo (T4) and took T3 instead. It wasn't brilliant but it was better than T4. I did try various combinations of NDT, T4, and T3, but T3 alone was the one I tolerated best. It wasn't until I had optimised my iron as best as I could that I tried T4 and was able to tolerate it. I switched to T4 only and started at a lowish dose (50mcg), then sometime later I added in T3. Ever since then I have raised or lowered my T4 or raised or lowered my T3, depending on which of them is too low or too high compared to which is furthest away from my optimal (which isn't necessarily the same as other people's optimal). I only raise or lower T4/T3 one at a time, I never change both at once. Then 6 - 8 weeks later I test again, and re-jig one of my doses again. These days I rarely test because my thyroid doses seem to be tolerable now.
Please note that some of us will take different doses of T4 on different days, if this is tolerated. I take 50mcg T4 on Monday and Thursday, and 100mcg T4 on the other days, so averages out at 85.7mcg per day. My T3 is always the same every day - it isn't a good idea to vary T3 dose.
Also, please note that I never pay attention to my TSH. My pituitary is completely flat and doesn't seem capable of producing enough TSH for my needs.
...
Results - T3 - 4.4 (range 2.4 - 6.0) 55.56% through the range
T4 - <5.4 (range9.0-19.1) Under range
TSH- 0.01 (range 0.35-4.94) Under range
Twice this month, my heart rate shot up to 210 bpm, tight chest and feeling faint.
When iron/ferritin are very low it can cause chest pain and tachycardia. So can low thyroid hormones.
In your shoes I would :
1) Optimise as many of your nutrients as possible. The ones we always start with are Vitamin B12, Folate, Vitamin D, and Ferritin (if ferritin is low in range or under range get an iron panel). If you post the results and ranges of your nutrients then we can advise on what supplements to take and doses to take.
2) Once your nutrients are well on the way to being optimal you could try taking T4 at 50mcg per day. Keep taking your T3.
3) Test a thyroid panel after 6 - 8 weeks. If your Free T4 is still under range or very low in range you need to raise that to 75mcg. Keep taking your T3.
4) If you aim for a Free T4 level that is 75% of the way through the range and a Free T3 which is similar then each time you test you should check how close Free T4 and Free T3 are to optimal and whichever is further away from optimal (in percentage terms) should be raised or lowered by a smallish amount. For T4 you would raise or lower by 25mcg per day if it is miles away from optimal, but by only 12.5mcg if it is reasonably close. Some people change doses by 6.25mcg per day if they are particularly sensitive to dose changes. T3 can be altered by quarter of a tablet per day if necessary - but as I said don't change both T4 and T3 at the same time. If you feel worse you won't know which change helped you.
Wow!! Thank you SO much for your informative reply! Someone that gets it!!! I have a friend arriving soon for the evening but I will be read this again in depth tomorrow. You are a godsend! I get married next year and I am tired of having spent the past few years with my energy in the gutter. I can't work full time -or- sustain any level of activity. Just the odd dog walk and social. Interesting to hear you say you couldn't tolerate T4 alone, same! T3 has the best result but far from great! I will try 'again' to get my pituitary glad tested. In fairness my endo did request my GP test this when I first signed up with her roughly 3-4 years ago. My GP said it was 'satisfactory' same as my thyroid! They are far from 'satisfactory' in my eyes.
Very interesting about your iron levels then reintroducing T4!
How do you take your iron? injections or a good supplement?
Apologies for taking your time. It is just a godsend to speak to someone who understands. I love this forum! xx
I don't take iron any more, but when I did I was taking one of the iron salts - ferrous fumarate 210mg. It can be bought without prescription from UK pharmacies. I could only tolerate it with food.
If I had my time over again I would buy haem iron. Do a search on the forum for "Three Arrows" iron which can be bought online. For most people it is far better tolerated than the iron salts apparently - I haven't bought any (yet).
Note that iron in any form should be taken at least four hours away from any thyroid hormones.
p.s. when you say you ignore your TSH, does that mean it was below 0.01. If I let my TSH dictate, my energy levels will be even worse than they are now, if possible!
Before I first started taking thyroid hormones (in 2013) my TSH had never actually reached 6. My Free T4 was 8% through the range and my Free T3 was 11% through the range. I had seen a couple of people on the forum quoting similar Free T4 and Free T3 to me, and in one case the TSH was about 10, and in the other case the TSH was about 30. That is why I believe I have Central Hypothyroidism.
Dr's suggestion was my TSH was too low and with my thyroid results are not healthy, sometimes with the thyroid, these symptoms can be cumulative.
Well, of course it was. That is their go-to solution and they don't look any further. But, the TSH itself has nothing to do with hearts.
Personally, I would say it's more likely to do with you being under-medicated. Your FT4 is well under-range and that might or might not be unhealthy for you as we all have different needs for T4. But your FT3 is too low. You probably need it more like 75% than the 50% it is now.
Hearts need a lot of T3. So, if your heart hasn't been getting enough for over a year, that could be the cause of the problem, so that doctor could be right about symptoms being cumulative. But it has nothing to do with the TSH. That is low because you are taking T3, not because you are taking too much T3.
So, before trying to reintroduce T4 - which probably wouldn't help anyway - try increasing your dose of T3. That's what I would do.
"Well, of course it was. That is their go-to solution and they don't look any further. But, the TSH itself has nothing to do with hearts. "
To be fair here, I don't read into the Doctor's response as saying "The TSH has caused your heart problems", more that they've questioned it, and the strange Thyroid test results.
I'm not sure exactly how read up on T3 Monotherapy we expect A&E Doctors to be? They might encounter people with Graves with suppressed TSH, and high heart rates/palpitations, and link that to Tachycardia (despite the normal T3 in this case), it's not a completely unreasonable response.
But when someone supplements with T3, breaks the TSH feedback loop, and has a T4 reading of a severly Hypo person, how would A&E doctors treat this fairly unique scenario, or make recommendations? Even most seasoned Endos would likely act wrongly.
But that's what they do say: suppressed TSH causes heart attacks and other heart problems. That's what they believe. Don't suppose he even looked at the other levels - they rarely do. And they believe that the FT3 is irrelevant.
Yeah, that's what they keep telling me. At the hospital, they told me "they didn't have my thyroid results back yet, but it was probably my thyroid meds being too high" This was because it was my second incident at A&E in a year with the same issue. I do seem seem to get the all clear on my other bloods re my heart.
I think quite a lot of us here have been to A&E at various points believing we're about to have a heart attack, myself included.
It's pretty clear that the way A&E departments deal with this is just check there's no imminent danger, and that the heart itself is structurally fine. Connect us up to ECGs, give us some drugs to calm us down, and then show us the door, recommending we go back to the GP/Endo for them to look at the Thyroid.
I don't understand the relevance of FT3 readings when a person is just on T3 medication. With such a low half life of T3, you're constantly riding the peaks and troughs throughout the day based on timing of medication. So isn't an FT3 reading basically dictated by the timing and size of the past dose, rather than giving some sort of reliable indication to your average FT3 levels?
I can see the relevance when someone is taking Levo, and the FT4 level is more stable, which inherently means a more stable FT3 reading.
How long do you think the half-life is? It's actually about 24 hours. And we always recommend leaving 8 to 12 hours between the last dose and the blood draw. And it's consistancy that counts: always dosing and testing in the same way. That way you will get a reliable indication of FT3 levels. It's not as unstable as people think. But, when on T3 only, symptoms are more important than blood test results. I haven't had a blood test since 2014.
Hi, I was led to believe T3 has a short life, around 8 hours. I always leave a good 12 hours before a blood test. You are SO lucky and I am really glad to hear you have got to the bottom of your thyroid issue. I do hope I can soon. It's been going on for a few years now.
I agree and get where you are coming from. I guess the T3 test is just an average gauge. I am at a loss really with all this stuff. I've been trying different meds and doses for sometime. My body doesn't convert T4 to T3 very well, if at all. However, I have many people, including my holistic GP tell me to take T4 as well and let my body do with it can with it. I have reverted back to this idea! It makes sense. I just need to stop getting heart palpitations and a tight chest when I do.
Thank you again for your advice! Much appreciated!!!
After having been on 50 mcg of T3 for best part of this year. I am now changing to 40mcg T3 and 50 mcg of levothyroxine. I hope this isn't too drastic a change overnight. I will stay on this for 2 months' before getting an 'advanced health assessment' end of January. You always have good advice which makes perfect sense.
I agree, despite my body not converting T4 to T3 very well. I feel my body still requires some T4. So I hope this dose sits well until I can reassess. My body definitely needs to be at 75% opposed to the 50%! Interesting you say, low T3 can have the same affect on the heart with it being cumulative. Very interesting and makes sense!
I understand adding in the levo, but why did you slash your T3 like that? 50 mcg T4 cannot possibly compensate for the loss of 10 mcg T3. And certainly isn't going to take your FT3 upt to 75%. So, why did you reduce it? Why not just add in the levo on top of your regular dose of T3?
Ah seriously! Thank you. I was worried that adding 50 mcg of levo on top of 50mcg of T3, would be too much. I was unsure how much T3 was in 50mcg of levo. I thought I'd play it safe initially. Admittedly, I am still on restricted energy these days. Thank you again!!! 😘
There isn't actually any T3 in 50 mcg T4. The T4 has to be converted to T3. It's a bit complicated but simply put I molecule of t4 contains 4 atoms of iodine - that's how T4 gets its name. To convert it to T3 one atom of iodine has to be removed.
Even in someone with perfect conversion only 30% of T4 will be converted to T3. So, if you're a poor converter it will be much less - impossible to calculate how much, though. So, you're unlikely to get much T3 out of 50 mcg T4.
I second this advice. Don't drop the T3. Just add in the 50mcg Levo. In fact when I did this I started with 25 Levo for a few weeks. Just to let my body get used to it again.
The TSH is a feedback hormone in response to you taking T3, how can that cause symptoms such as tachycardia?
As others have suggested, the root of your problems may lie in your low T4 and your T3 levels are also a bit low, especially considering your T3 is only 55% through the range. Thyroid hormone deficiency can weaken the heart's contractions and relaxations, which can lead to a lower heart rate. However, in rare cases, it can cause arrhythmias, including ventricular tachycardia.
How are your iron levels? Anaemia can cause tachycardia, or a rapid heart rate, because the heart is working harder to compensate for low oxygen levels in the blood. So perhaps also check your iron levels and correct if low.
There are members that are on T3 therapy only, but it might not be the right long-term therapy for you. Maybe try to add some T4 in again and see if this may help (together with looking at your iron)?
Thanks for replying. I agree, I always thought TSH was a hormone response to taking T3. Hence, I wasn't concerned it was too low. Advice from a holistic GP!
However, something is causing these sudden raised heart rates, tight chest and breathlessness, which is hard to ignore.
I have introduced 50mcg of levothyroxine as of today, whist reducing my T3 to 40 mcg. I know I've taken this dose before and l struggled with my energy (unable to work full time) but I don't like to make too big a change overnight.
That's interesting about taking too low a dose equally causing a tachycardia! I do take iron tablets daily as after receiving my NHS bloods, I was informed my iron was fine (mid range) However, interestingly, the holistic GP, thought I was almost anaemic, upon looking at the same results. He mentioned that the NHS range is a poor guide. He gave me two B12 injections that day.
Good advice and makes perfect sense!! Thank you for taking the time to reply x
There are other factors that can cause tachycardia such as stress, certain medications (do you take other medications?), electrolyte imbalances (changes in sodium, potassium, calcium and magnesium), high blood pressure...
Did you do some strenuous exercises recently? Exercise requires a lot of T3, so if your T3 levels are already low and your thyroid cannot produce T3 on its own, this may have left you quite depleted and could have caused the irregularity.
Just check that there are no other influences besides the thyroid hormones that could have been responsible the tachycardia.
Thank you Tina! I don't take any other meds which would effect my thyroid meds. I do take iron and vitamin D but I'm led to believe this will help me.
I sadly don't do any strenuous exercise. I wish I could. I struggle to sustain light exercise, albeit my weekly stretch class, and it's killing me. I used to be so active. I'd love to be on my mountain bike again but I just don't have the energy. I sometimes manage 10-20 min easy cycle on my static bike in the garage on a good day.
I have booked myself in for a thorough medical assessment looking at my vitamins and hormone levels as well as thyroid. Hopefully I can make sense of this.
Thank you again for your help and wonderful advice! xx
I’ve been having fun with something similar this year (it started in May). I too ended up in A&E, and similarly, my suppressed TSH was questioned (I take NDT) and implied to be the cause. I’m now very sure it wasn’t/isn’t.
For me, I am now 90% certain it’s a “not quite finished with you yet!” menopause symptom. It happens if I get over-tired (there’s the link with thyroid hormones I guess), if I get over-stressed or, as HumanBean’s mentioned, I eat too much sugar.
Interestingly, the less attention I pay to it, the sooner it slows down. I find I’m far too tuned into what my heart is doing at the moment, say when I climb stairs or find myself hearing my heart beat when my head is on the pillow.
For me—and obviously I’m not trying to say this is true for everyone because of course it isn’t—for me, I can experience a panic response hearing a slightly faster heart rate that can turn into full blown tachycardia. If I tune into it, it can stay elevated for quite a while and I feel absolutely dreadful.
However, if I plug in earphones and play music loudly or plug into the television the moment I notice my heart rate is on the rise or find another way to distract myself, like calling a calming friend, it settles back down within a few minutes.
I find that immensely reassuring because I think if there was something really wrong, it wouldn’t settle down. Plus all the tests I had done showed there was nothing wrong with the rhythm, it was just fast.
So I’m now working on trying not to over-react (harder than it ought to be but I was so scared that day I ended up in A&E). It’s been an incredibly stressful year for me personally and I think that’s played into this too.
As others have said, check out your other results and make sure ferritin, B12, folate and Vit D are all optimised. And maybe keep an eye on your T3 levels to see whether dose adjustments are needed.
Thank you so much for taking the time to reply and share your experience.
Although, I am sorry to hear you are on a similar journey. I am at a loss to be honest. It is such a mindefield isn't it. I do eat too much sugar (mainly when I am exhausted, for a boost - not healthy I know!) I hear such conflicting advice from professionals but they all blame my thyroid and in particular my low TSH.
However, I have always valued the advice on this forum and there is a general feel that I need to re-introduce T4. This I agree with. I am booking myself in for an advanced health assessment in January. Yet more cost, but I need to get this resolved, somehow.
I have now reduced my T3 to 40 mcg (instead of 50mcg) and introduced 50 mcg of levothyroxine. I will get this re-tested in 2 months'. I have been on this dose before and it left me exhausted so I came off levothyroxine and upped my T3.
My ferritin, B12, folate and Vit D are all ok according to my bloods 6 months' ago. I am going through the menopause too! I am sure this complicates things further!
I have had a few of these incidents (on average 2 or 3 each year) and as you say, try to take slow breaths and keep calm. It is hard though, as I tend to wonder it won't ease off after 15 -20 mins.
I think the things to hold on to are: the heart is actually amazingly resilient, it can cope with lots more than you’d expect. And secondly, your success rate at getting through those racing heart episodes is 100%. ❤️
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High T4 low TSH
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TSH and T4 numbers haven't budged
