Palpitations and irregular pulse - why?

First thing in the morning my blood pressure is usually around 109/58, and pulse 60 or 61, temperature varies from 35.6 to 36.6 and never higher.

In the afternoons and evenings sometimes I have sudden racing pulse for up to a minute or two (rarely more) and then it stops momentarily and re-starts at a more normal pace. It is frightening and I don't know if it caused by the heart valve problem which I have had since I was thyrotoxic 30 or more years ago, or the enlarged heart which was spotted in December after 6 years of thyroxine starvation, or whether it is actually the result of still not being adequately medicated.

I DO know that if I went to my GP he would say it is because my Levo is too high and reduce it, but I do not for one moment think that. Has anyone any thoughts on this?

I am planning to replace some of my Levo with T3 to see if I feel better, so once I get my T3 result I will put it on here hopefully to get some feedback (and reassurance). Obviously with an enlarged heart I don't want to over-stress it, I just want to swop 50 of the Levo for half a 25 of Cytomel. I am already taking COQ10 and B12 in a spray form under the tongue. I haven't had the money to test vitamins and ferritin etc, that's the next job if the T3 does not improve things.

Thanks in advance for any suggestions or advice that you can give.

19 Replies

  • Levothyroxine (I wasn't taking a high dose) always gave me heart problems, for which I had to call the ambulance about 3 times and had many ECG's. During the day it was similar to yours - pulse suddenly rising. During the night it was a nightmare and they gave me betablockers.

    No problem with my heart as soon as I stopped the T4 and switched to T3 . My heart hasn't looked back and neither have I.

    I think sometimes there is a sensitivity to binders/fillers.

  • That's interesting. Perhaps I should consider that, although I didn't get it quite as often when I was on 150, but I am going to keep an open mind and see how things go.

    Thanks very much


  • Hello Marie,just to say I had the opposite to shaws,I had the palpitations before starting levo and now they seem to have lessened greatly almost gone. I to have enlarged left side of heart

  • That's interesting, too. How much are you on? I have been on 150, reduced for 6 years to 100, now up again (at my insistence) to 125. When I was on 150 I don't remember having any problems like that, it was only when I was reduced to 100.

  • Hi marram I have only been on it for 12weeks so novice really! But definitely palps and irrational beats have reduced to virtually nil I was told my LVH usually caused by high bp or the heart itself but echo fine and not being treated for high bp! I didn't get explanation of what else may have contributed to it but was very shortly after started on levo,so still non the wiser really!

  • That's great news for you. I hope the news will be good for me too :)

  • Hi This could be associated with thyroid levels as stated. However, the most important first medical test is to take HR ( pulse) 3 times a day , to include these times when an intermittent problem. Chart. Notice not just high, not too important, but uneven, easy to feel, do not use a machine, as all untested and cardio`s all say useless. Do this for 2 weeks, if looks as I say, sometimes, it is always intermittent to start with., See GP and ask him to arrange a 24 or better 7 day heart monitor, at home. This does non stop ECG`s, a normal ECG will not do as this is an intermittent condition. If it is something wrong, likely obe Atrial Fibrillation ( A. F) only way to diagnose it. Not too serious but if you have this essential to be on anti coagulation to avoid clots. This is nothing to worry about but you need to know. If the initial Heart rate ( pulse) does not show swinging, then you do not have it. I hope that is clear, just make sure. Thyroid disease can bring on onset of A.F at any age.

    Best wishes,


  • Thanks Jackie.

    I am already on Clopidogrel because when I first had my thyroxine reduced to 100 from 150 (which I was really well on) I had three mini-strokes within 2 months. The doctor never, ever connected it with the thyroxine reduction although now I am absolutely certain that those mini-strokes were caused by AF and also they were the result of thyroxine being reduced so drastically in one fell swoop - reduced by one third in one day!

    I have had all sorts of tests and investigations over the last two years - as you do - and there are no blockages in my arteries, they just said I have a heart valve which is not fully functioning. This is something which was picked up at a medical more than 7 years ago and it was asymptomatic at the time. I have only had this problem since that accursed reduction in the thyroxine dosage!

    My machine is exactly the same as the one my doctor uses to measure my BP, and it says it is clinically validated, whatever that means! It has an irregular heartbeat alarm - I have noticed it before I got it anyway when taking my pulse. sometimes it does a boom-boom (rest) boom-boom (rest) boom-boom-boom (rest) boom-boom and then it settles. I will keep taking my pulse manually as you suggest when I feel that heaviness in my chest, I usually find it's racing and then settles.

    I actually bought the machine to do my BP because the doctor after making me angry with his drivel suddenly decided to take my BP and said it was too high, and I need to reduce the thyroxine again. I want to show him that my BP only rises when he starts trying to kill me.

  • Sorry rushes, may only put my ,long reply on the main question, not sure now, so check ,if not received.


  • Hi Well first, you can have perfect arteries, I do , only bit of my heart that is OK. You really, need Warfarin for AF not clopidogrel for strokes Vital to see a cardio who deals with electrics, cannot remember the name. I saw 12 and had 2 cardiac arrests( then lucky), before the correct treatment, and left with dire things, Do not let that happen to you. You also need your blood tests for the electrolytes, for everyone must always be in range, can cause the most serious arrests, like my 4 and .3 acute renal collapse. They are, Potassium and sodium, ideally potassium 4 ( U`s and E`s),Magnesium, tiny range, never take without weekly blood tests, script only , In food fine. Calcium for corrected , many repeats if on vit D, as it makes it go up. I made a lot of enquiries and the manufacturers say HR machines never tested only BP machines. BP often actually goes low while having a A F attack.I see the top cardio ( 2 ) in this in the country as so many conditions now and an iCD. They all say so long as you have enough treatment for thyroid ,to keep in range, and feel right, that is fine.but you have to be under an endo,make sure it is a good one. I hope this helps, please insist on seeing the right person. check all the best have CV`s on line saw in local hospitals ( in patient) and I do, this is on my own brilliant cardio`s insistance!

    Do get back to me if I can help further.

    Best wishes,


  • Hi Jackie, since starting on Clopidogrel, I have not had any mini-strokes, that's now almost 5 years, it was when he first dropped my Thyroxine, I think it was too much of a shock to the system.

    I really hope that I will not have to go on Warfarin, I have a Spanish husband and he could not live without his Garlic. I understand you should not have garlic if on Warfarin, although whilst garlic does prevent blood clots in a test tube it does not appear to have the same effect when consumed, so I am not sure why it is contraindicated.

    He first put me on Statins (because of the cholesterol going from 4.7 to 9.7 in two months) but I could not get on with ANY of them so I stopped them of my own accord, in preference to going to bed and quietly fading away.

    The TIAs did not stop until I took the Clopidogrel - so the statins were a waste of time anyway. My cholesterol has remained high (although the balance of HDL:LDL was good the doc said) going as high as 10 at the end of last year. However, he increased my thyroxine to 125 in December and at the last test my cholesterol had already come down to 8.

    Of course, the doctor refuses to acknowledge that it was the thyroxine reduction which caused all the problems. Although I had been well and fit for 23 years after my TT, on 150mcg Levo.

    Now, I know I will have to be cautious because some damage has been done over the last 6 years of Thyroxine starvation.

    If I continue to have problems, or I am worried, I will certainly bear your advice in mind, thank you for all the information.

    Marie XXX

  • Hi Jackie, I'm interested about sodium and potassium levels, I had mine done short while ago, my bp and pulse since changing dose has shot up to 106 pulse. What is the right level of sodium and potassium in bloods? My potassium was only 2. Something just in bottom of normal range and so was sodium, I'm always craving salt.

  • Hi minus,

    It is important to have sodium levels just in normal range.The normal Potassium test should be 3.5 to 5.3. The ideal being 4. With low Potassium it is common to also have low sodium.

    I hope that helps.


  • What is ideal sodium? My potassium was low in the range 2. Something. Nothing by go or endo was said about results, cause its within the range they don't comment.

    Took my pulse today and its 101

  • Hi Minus,

    Sodium should be low in range which is usually 1.3 to 1.33.

    I think you must have been wrong about the potassium as it could not be that low. Worth having a magnesium test too as if below it`s tiny range then you need some to help the potassium. Potassium is in bananas, kiwi and tomatoes.

    If doing pulse you need to rest for 10 mins first. Also do not have any coffee even 30mins before. 101 is a little high but depends what you are doing.


  • Hi Marie, Garlic is good for the blood, only very few things eg grapefruit dangerous, look at the WEB, Statin,, well I need them because my cholesterol has to be very low, much lower than the normal , it normally should be below 5 but often under treated hypo can cause it, when hypo OK so is the cholesterol( often the BP too)With just AF there is a simple, new drug for AF, brought out especially for that. it is more expensive, not too new, and does not require blood test and is considered by my very good Haemaologist, he is very involved with it. Just, not suitable for all my heart conditions especially VT`s.

    If I can help further send me a PM. Do remember the important blood tests, especially Potassium.

    Best wishes,


  • Can I ask, Jackie, why you think cholesterol should be below 5 in general?

    It's my understanding that the figure of '5' came about via the drug cartels that developed statins.

    They need to sell their drugs and it is far more profitable to treat patients with what was a normal cholesterol level (above 5) to get it below 5'.

    There is research that proves that you are more likely to die of a heart attack with lowered cholesterol by statins, than to leave it be.

    Yes, untreated hypo causes cholesterol to raise and also BP as they did in my case.

  • Once my doctor had accepted the fact that I was never going to take statins anymore, he actually said to me that my Cholesterol was in the right balance and my heart attack risk as a never-smoker and light drinker was minimal. It's weird how he changed his tune once I told him I would jump over a cliff rather than take statins.

    I have a bit of a mysterious family history and the risk was too great for me. I was getting so disabled I think I was close to rhabdomyolysis, as soon as I stopped the statins I started to feel better. When I was taking 150mcg of Thyroxine, my cholesterol was 4.7, yet after being reduced to 100 it went right up to 9.7 and even 10. Now I've had a slight increase it is going down again.

    I wouldn't like to tell anyone not to take statins, it is entirely for the individual to decide, but newer studies seem to suggest that the heart attack risk could be greater with statins because they deplete the body of COQ10 which is what the heart runs on. I have found that my own wisdom seems to be doing me more good than the doctor's wisdom - if he had his way, I would be on 75 mcg of thyroxine, statins, blood thinners, antidepressants, sleeping tablets, strong painkillers (which made me vomit), asthma inhalers, nasal spray, antihistamine tablets, PPIs.

    Since my thyroxine increase I have stopped the inhalers, I stopped statins anyway, refused anti-ds , stopped the sleeping tablets, stopped the painkillers, all i'm taking now apart from my thyroxine is Clopidogrel which I am taking only on mon-wed-fri, and PPIs because of the clopidogrel. I hope I can stop the clopidogrel if I am well, and then I will be able to stop the PPIs as well. Then I will be back where I was before this doctor messed with my thyroxine, except that now I have an enlarged heart. But I have read somewhere that if you take it very carefully even that can be reduced.

    I am taking COQ10 at the moment because I want to give my heart every possible chance to get better. I might continue with that because older people do tend to have reduced levels of COQ10, so it's a bit of an insurance.

    If the long-term plan works, I will have my cholesterol back to 4.7, and be taking only Thyroxine (and possibly T3) and COQ10.

    Then, if, after all the precautions I have been taking, I continue to have heart problems, then it's back to the drawing board!

  • Hi Is the Cardios who stipulate below 5 based on research but not the only trigger factor.


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