Pounding Heart - Is this a common Hypo symptom? - Thyroid UK

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Pounding Heart - Is this a common Hypo symptom?


For the last 3 months or so I seem to feel my heart pounding probably about 90% of the time. It seems to be worse when I lie down so consequently I'm not sleeping well. My pulse doesn't seem excessively raised - mostly it's around 60 but sometimes it does seem to speed up for no reason. I also get aches and pains around my chest and arm (left side only). I've had several panic attacks because these symptoms are really frightening me and I'm worried there is something wrong with my heart. My gp thinks this is all caused by anxiety but I think it's the other way round. I am feeling really unwell at the moment and I know I'm hypo - Last bloods from September were tsh 10.7 (0.27-4.20), ft4 13.3 (12-22), ft3 3.1 (3.1-6.8).

33 Replies


Yes i get the same heart pounding and some heart flutters which are worse when i lay down,i have also noticed they happen when i have eaten ..im.having a 24hr ecg done soon. But i agree its frightening especially when you get left sided pain. I remember reading something a while ago that said that missed heart beats and flutters can cause the muscles down the left side to react. Both under medication and over can cause similar symptoms. Maybe its worth asking for an ecg to put your mind at rest.

Hi A normal ECG will not show this, as an intermittent problem, usually for years before permanent. The only way to diagnose is as I have put in the answer to "Any one have whooshing in their ears.?"Yours are the common symptoms of this.

Best wishes,


Hi, I am hypo and I also have palpitations. I had them long before I was confirmed with hypo and over space of 2years had heart monitors and ultra sounds of the heart and nothing wrong. I'm on 75mg now and I still get them but not as often and mostly when I'm extremely tired. I have asked my gp to increase my dose but won't as he says could make me hyperthyroid and palpitations worse.

Im going to see Dr. Peatfield because i feel that my thyroid problem as much alot of pressure on my adrenals. palpitations and flutters can be a sign of adrenal fatigue as the thyroid meds are trying to speed up the bodies metabolism and the adrenals can not keep up which in turn many organs in the body including the function of the heart.

Jackie in reply to Joanie76

Hi GP could well be right. Make sure you have had a 7 day monitor, not just a 24 hour one, it may not have been enough. Also should see a cardio dealing in rythym problems, large teaching hospital, specialised.


Increasing my dose of Armour stopped the nighttime pounding. I think when you are overmedicated you also have breathless, tight chest and fast palpitations....very different from under.

Hi A, F often worse at night. See my reply to above "Any one get whooshing in the ears?"Palpitations the more normal symptom., to start with.. A. F needs ruling out.

Best wishes,



Have you been diagnosed with hypothyroidism and, if so, what dose do you take? You have stated above some clinical symptoms and if you have been diagnosed with a TSH of 10+ in September, I would have expected the GP to have checked your bloods again after six weeks to make sure TSH it is reducing and also increasing your dose. Pounding heart etc can also be due to being undertreated. It can also be due to acclimatising to levothyroxine.

130396 in reply to shaws

Hi Shaws

I'm getting a pounding heart at night too.

You've probably seen my recent posts.

Im now on 75mcgs levo and 25mcgs t3.

Am planning on increasing t3 by another 5mcgs tomorrow.

So far I've not had any improvements on my symptoms from when I first posted here since introducing the t3.

Any ideas how long it might take for my symptoms to start easing up

Thanks P

Rose 🌹

shawsAdministrator in reply to 130396

Hi Rose (I like your red rose beside your name).

I have looked back on a couple of your previous posts. Pounding heart can also be due to too large a dose or sensitivity to the fillers/binders.

If you've not found T4 helpful at all to you I would be tempted to just switch straight over to T3 only (being mindful T4 would take about 6 weeks to leave your system altogether).

You are already taking 25mcg T3 which is equal in effect to around 75 to 100mcg of levo. You are increasing by another 5mcg tomorrow. Make a note of your pulse and temp about 3 times a day. (The Basal Temp Test first thing is a good way although none are perfect)


I would then raise T3 by 5mcg about every 2 weeks till you feel good. If not drop back to your previous dose.

If you felt best on NDT you could also go back onto it and I am assuming your heart didn't pound either.

If you have an Endo you can ask if you can have a trial of T3 only for 3 months at least.

I hope you feel better soon. It is trial and error till we hit a dose/meds we feel well on.

"I am not a medical professional and this information is not intended to be a substitute for medical guidance from your own doctor. Please check with your personal physician before applying any of these suggestions"

130396 in reply to shaws

Thanks for replying.

I've been taking my temperature for a little while with a mercury thermometer taken under the arm in the morning.

It usually starts about 36.2 (sometimes 35.9) it rises steadily through the day to about 37.0 then drops back down to about same as the morning ones during the evening.

I then did it orally with a digital one since going on t3. It starts out at 97.1 and gets to 98.5 in afternoon then drops again.

I noticed after increasing the t3 last week that it did on a few occasions go above 98.6 but only a little bit and it seems to have regulated again now.

My pulse on resting is 72-76 but when I've been getting this pounding heart in the evenings it has been 86-90.

Im unsure why the heart pounds in the evening but I have a feeling it's because the beta blocker I take at night (which is slow release and supposed to last 24hrs..... But doesn't) I think it's running out

The reason I think this is because when I used to take it in the mornings I used to Wake up in the night with my heart pounding. About 3-4 hrs before morning dose was due.

Im not sure about going totally t3. I'm taking same brand levo I always took. Also not keen to go the NDT route again.

I suppose I'll need to see how I feel andvwhat my next blood results are

Would I know quite soon if the extra 5mcgs was too much.

I know when I increased before I felt a bit too hot for a few days and my bowels were a bit loose for few days

Lol. I've now gone constipated again!!

Thanks P

Rose 🌹

shawsAdministrator in reply to 130396

Your temps look fine and it's good that we can make a choice of whatever thyroid hormones makes us feel well again.

Betablockers can have a slight affect:-

Beta blockers and corticosteroids that only inhibit the peripheral conversion of T4 to T3 interfere minimally with thyroid function test results. Propranolol hydrochloride (>160 mg/d), atenolol, and metoprolol tartrate produce small reductions in total T3 levels.


I don't know if you take your hormones all at once or if you split your doses. Maybe if you took them once daily it might relieve your pounding later in the day. Just a suggestion.

If you're taking a reasonable amount of thyroid hormones the effect shouldn't run out. T4 as you probably know has a half-life of 7 days. T3 is effective once in our cells and the effect lasts between 1 to 3 days.

130396 in reply to shaws

Hi Pat.

Yes I do split the dose of t3.

10mcgs on waking

10mcgs 1pm ish

5mcgs about 3pm.

I was going to increase again today but have decided to wait a few days.

My temperature is looking OK and I'm worried about going too high if I increase

I've still not had any symptom relief yet though and it been almost 6 weeks.

Rose 🌹

shawsAdministrator in reply to 130396

Dr Lowe took 150mcg of T3 once daily for Thyroid hormone resistance and this is an excerpt:

Third, the leaflet on Cytomel pharmacies give patients when they fill their prescriptions states, "POSSIBLE SIDE EFFECTS: NO COMMON SIDE EFFECTS HAVE BEEN REPORTED with proper use of this medication." This information is accurate—when plain, full-strength, one-time-per-day doses of T3 are used properly, there are no adverse effects. The only adverse effects occur when a patient takes a dosage that for her is excessive. With Cytomel, if overstimulation occurs, it can be stopped with one or two small doses of propranolol. Or the patient can simply reduce her dosage of Cytomel the next time she takes it. I want to emphasize, however, that when our protocol is used properly, there is no overstimulation to be avoided by using timed-release T3. The protocol has safeguards against adverse effects.

And finally, why do I specify that the typical patient use one full dose of non-timed-release Cytomel for life? Because extensive testing has shown that this is safe, effective, and most economical—when used within the context of our entire protocol.


130396 in reply to shaws

Hi again

I've read all that article on Dr lowe.

What do you think about my temperatures being OK.? Sometimes I feel a bit overly hot ( but that's how I've always been really)

Also. Why do you think I haven't had any improvements yet after 6 weeks?

shawsAdministrator in reply to 130396

I cannot answer that question as every single person responds to different doses/meds in all sorts of ways. I can only tell of my own experience.

My original prescription was for levo at 25mcg, 50mcg then 75mcg, 100mcg. Still complaining - Endo added 10mcg of T3 to a reduced 25mcg levo who didn't like my next blood tests and told me to stop T3. I told her I couldn't do that so she reduced T4 by another 25mcg of levo. I knew the combined dose wasn't sufficient. Asked to be switched back to GP.

I saw two private doctors who were recommended by Thyroiduk.org.uk

I then was able to source my own T3. As I was already on T4/T3 I stopped T4 and took 25mcg tablet and then increased by 1/4 tablet about every 2 weeks keeping notes of how I felt (particularly heart/pulse/temp.) Heart was affected before being diagnosed and also with levo, i.e. jumping/palps/missed beats etc.

T3 calmed my whole system down, no more palps and with each increase I felt an improvement.

Because I took my dose once daily I was better placed to know exactly how each increase worked and could feel more or less within a short time whether I was taking too much or too little. If too much I just dropped back to the previous dose. When l I had no more signs/symptoms that's where I stayed. I am now on 1 1/2 T3 (approx 37.5mcg T3) although some may need a higher dose. I'm happy, symptom free and pain-free. I even missed one day's dose and it didn't affect me.

I am aware that sometime I may have to adjust but that would depend if symptoms arose but would have a blood test first.

My journey to finally being diagnosed with a TSH of 100 took about 5 years (not one GP/specialist took a blood test)then onto levo to feeling well must have taken about another 5 years in all.

I had also taken NDT and one suited me well.

I was diagnosed 4 years ago (but unwell and undiagnosed for at least 4 years prior to this), have been on levo since. Currently on 75mcg levo + 10mcg T3 (the T3 was added by endo about 18 months ago). I know I am undertreated - it's all a bit complicated and probably partly my fault. The endo's response to last bloods was to increase the levo by another 25, but I have been trying to get them to increase the T3 instead for the past year. I am awaiting a reply to a letter I wrote to the endo asking for this. Gp will not do anything unless endo says so. Over the past 4 years its just been a case of TSH up = increase levo, then TSH suppressed = decrease levo and so on and so on. Meanwhile I'm not getting any better...... I did have an ecg and 24 hr monitor in 2011 - both were normal.

I saw Dr P earlier this year and began his protocol involving reducing my levo dosage by half, taking Nutri Thyroid and Nutri Adrenal Extra. Plus treating Candida. I followed this all by the book for about 3 months but made no real improvement - Dr P advised more T3 so I went again to my GP to try and get more (as I was worried about going down the road of self treating for various reasons) This is where it all went wrong because my tsh was very suppressed (presumably due to the glandulars) so this set off a chain of events - referred back to endo, lots of bloods done including TRH test. I stopped all the glandulars prior to these tests and basically fell off the wagon where Dr P's treatment is concerned. It has crossed my mind that either stopping the NAX in July or falling back into bad dietary habits may be playing a part in this.

So I'm stuck really, If I go to my gp without a reply from the endo - I will just be told to increase my levo. If the endo says no again to more T3 then I will have to go back (humbly and apologetically) to Dr P and start again on the self medicating route. I am just despairing now - this stuff with my heart is possibly the last straw. I suppose I was just hoping that everyone would say that yes, this is just because you're hypo and I would feel better..........wishful thinking I know

Hi NicolaJane,

I know you don't want to hear someone else's problems as you have enough to deal with yourself. I just wanted to thank you for your post as am really suffering from these heart palpitations especially at night and I am convinced it is my thyroid but I haven't been diagnosed. 18 months ago I was ill with all the hypo symptoms and when my thyroid was checked they found a nodule on the right lobe but my blood tests they say are in range.

I have had an ECG which was normal and I'm waiting for the heart monitor ( three months!)

My last blood test results are: TSH 3.65, then TSH 3.28 FT4 14 and then TSH 2.93 FT4 15.3

I have felt mildly better on multi vits/mins and I have read that there is a connection between minerals and vitamins and a struggling thyroid. All i want is someone to take this seriously as desperately want to feel better. My mother had the same problem at my age and was on Levothyroxine for the rest of her life.

My I ask how you were diagnosed? Did you have blood test results that were out of range?

nicolajane in reply to myanne

Hi myanne, thanks for your reply....

getting diagnosed can be a real difficulty for some of us. In my case it took years because I had already been diagnosed with depression so they put all my symptoms down to that. In the end I was very unwell and funnily enough it was severe joint pains that got me finally diagnosed (once xrays and blood tests had ruled out arthritis). I think we are all different - when my tsh is at 10 I am very unwell, but some people can have their tsh up in the 50's with no symptoms. I think It's just sheer persistence with your Gp - I have found that the only way to get any help is to just make yourself a pest - not easy I know, especially when they can be so condescending. If your mum had the same problem use this as justification, they usually seem to take family history seriously. Trouble is they wont diagnose until the tsh is clearly out of range.

On the other hand, it could be another hormonal problem - I think these symptoms are also common around perimenopause?

Vitamins and minerals are good, also palpitations are sometimes caused by anaemia or low B12 (you could ask your Gp to check these?). In the meantime you could try a thyroid supplement like Nutri Thyroid? Hope this is helpful

Hi Nicolajane,

Thank you so much for replying. You are right - the symptoms are similar to menopause in some ways and that is the problem. Also I had a very bad year last year so my anxiety levels were quite high when all this started. However, I knew there was something very wrong with me when I just couldn't seem to do anything and just holding a conversation was difficult. I was totally wiped out. On top of that I had trouble swallowing and it was that that made my GP send me for thyroid tests which showed the nodule. I instinctively know and feel that it is my thyroid as I feel so different . The palpitations are the latest symptom and this is really worrying me. I also have joint pains in my knees in particular but I have put that down to arthritis. My GP did do blood tests when i said that my palpitations decreased after taking multi vits/mins. I don't think he did B12 but I think they can tell that by the size of the red blood cells. Everything was low normal really but there was a low TIBC which measures how the iron is carried around the body. It is usually low if you are fighting a chronic disease and therefore this has made me even more certain of thyroid trouble. However my GP isn't concerned so I must wait and maybe when get my nodule checked as I do every 6 months I could ask for another blood test. I just don't feel right - not myself at all.

I do think it helps to talk about these things and I really appreciate your feedback. I didn't know about nutri thyroid so that is really helpful - thank you. I do feel your frustration and really hope your situation is resolved and you start feeling better soon. Nothing's easy is it!

Many thanks.

PS Do you think my TSH etc are ok? If you say yes that's fine - I just need to know from people that really do understand the situation from personal experience. Thanks again.

It makes me so frustated and angry that once u've been labelled with 'anxiety disorder',nearly everything else (symptoms) r put down to that!i have had various 'heart symptoms' and all they offered was a quick ecg which is inadequate to say the least.i have untreated hypo/hashis and i KNOW my heart is not as it should be.

danceforever in reply to cloud1

Thye shouldn't label you with 'anxiety disorder' as they should know that is what you get with thyroid problems. I get that too, but have felt alot better in control since using natural progesterone. that is much better than trying antidepressants. Its calming and eases the pains that go with hypo.

Sometimes you get those symptoms from low blood pressure or low blood sugar. they naturally occur when you have hypothyroidism. They all feel scary when they happen, but its not always anxiety. your sugar levels drop off and on all day and night with hypo, as does you blood pressure. I get severely low blood pressure from hypo and my heart races often. the best way to feel better is to have a salt drink once or twice a day. this will boost your energy levels too. google low blood pressure and salt drinks..don't have salt drinks if you have high blood pressure.

Thanks, yes I have been told a few times that my blood pressure is on the low side. Your comments do make a lot of sense - I've been convinced for years now that my hormones are a mess and wondering if I'm oestrogen dominant. My symptoms are worse at certain times of the month. However i dont really want to start taking anything unless I know for sure what's going on there.

Blood sugar - well, I'm starting to think now that I might be hypoglycaemic (I'm praying not diabetic) as I've noticed that I do feel sick, shaky and anxious when I get up. If I force myself to eat something i think I feel a bit better. I will ask for a blood test when I go to the doctors next.

I think I really need to get some tests - adrenal stress, female hormones, probably reverse T3 but it's a case of finding the money for all this stuff (I live on my own and just about survive on Employment Support Allowance). I just get so upset and angry that doctors can't or wont help.

Thanks for reply Danceforever(like the name by the way;i love dancing too;though havnt felt like it much since autumn..cos i get S.A.D.).I have used natural progesterone cream but not sure if used right dose for me;it was a little helpful ,i think,with periods,but i stopped couple months ago cos got worse pmt(tummy ache;which i dont usually have and depression).I might give another go but have read that nat prog cream builds up in ur tissues and so is not healthy;long -term.Can i ask u what dosage u use and what times of month?I do take 5HTP for moodwhich seems to help.

I do have low blood pressure and slow pulse;and i too tried salt water ,'on and off';just not sure if it helps or not.I do have blood sugar problems too,as,if i dont eat regularly/frequent meals/snacks i get shaky,lightheaded,anxious.The heart symptom isnt racing heart (though i have had that on rare occasions in past)its a slight discomfort in heart,mostly ,and weakness of left arm but can be bit worse at times(esp with pmt;feeling bit more weak/pale.perhapsits iron deficiency too).The 'funny ' symptom i get is that my heart does race a bit if i lie on myright side when about to sleep.

nicolajane in reply to cloud1

Cloud, your symptoms sound very like mine - that feeling of discomfort around the heart and the aches in left arm are familiar to me. I've had this on and off for about 3 years. I'm pretty sure this is all hormonal, what we need is a doctor who understands thyroid problems and how all the other hormones, adrenals etc., are affected and out of balance. Question is where to find one, if they exist. NHS endocrinologists don't seem to know or care about this stuff. See my reply to danceforever re blood sugar/blood pressure...

Just forgot to say;the gp wont diagnose hypothyroid;because tsh /T4 is in range.(although i have v v high thyroid antibodies;aswell as lots of hypo symptoms.)It sucks so much ,that they just dump 'anxiety ' label on u and so i just ferl that anything i go in to talk about is dismissed,mostly.Its like they're basically saying i am a hypochondriac.No ,I 'm bloody not; its HYPOTHYROID!!!I would want to shout at them...but i dont.

nicolajane in reply to cloud1

totally agree, just makes you want to bang your head against a brick wall.

Nicolajane,i've always said that going to the gps feels like hitting my head against abrick wall!Funny,we've got quite alot in common.i too have had the heart symptoms for about 3/4yrs.Also ,i was initially diagnosed withh depression;which i didnt dispute at the time because i didnt have a clue that all the symptoms i had could be thyroid related..i didnt even know what a thyroid is!!It was through a magazine articlr about hypothyroid,that a 'bell rang'.!(and i had thyroid tested ,but am just about always been 'in range';except for the v high antibodies).I live on my own and am on ESA too;yes,it is difficult to afford tests etc..i have only done the adrenal home test ,recently.

Oh,about what u say that its 'hormonal',well it is in the sense that thyroid ,adrenals etc production of hormones is disrupted but it doesnt mean that the heart is not starting to be 'diseased' by the lack of 'essentials'.Moreover,itsawell known fact that untreated hypothyroid can lead to heart disease and that it weakens all ur muscles;incl the heart of course.I have v poor blood circulation too.

Hi! I am experiencing the EXACT same symptoms. Doctors think it is anxiety but I believe the heart pounding is causing the anxiety and panic. Did you ever find out what this was from? I'm really worried and it seems like I'm going to have to live like this forever :(. Please let me know what you found out or if it ever went away



nicolajane in reply to SaraAnne4

Hi Sara, I'm sorry you're going through this I know how horrible it is. To be honest I never got any answers from my doctor, and like you I was told it was anxiety. I have actually ended up taking a low dose of antidepressant which has helped me. There are other things you might want to check - iron levels, including ferritin test as low iron can cause this, also low b12. I have to take both of these. I am also on a t4/t3 combination, I find I get on better with some t3.

I'm sure it is thyroid related, but could be that you're not on enough or too much thyroid hormone too. Could also be adrenals, I don't know much about that but there's lots of info on here if you search for it.

I hope this helps a little....


SaraAnne4 in reply to nicolajane

Hi Nicola,

Thank you SO much for your response. Every day is a constant struggle and it is so scary to think I may have to live like this forever. Has your anxiety and pounding heart gone away?

I went to a psychiatrist and they gave me a low dose antidepressant as well but I truly think it is something else as I am not really stressed about anything. I will definitely try all of these You are so kind to have responded, it means so much! Any kind of answers right now help.

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