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.
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.
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.
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.
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.
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.
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