I have hypothyroidism and I know this can cause a slower heart rate. Mine usually sits round 45 bpm but can be as low as 35/36 according to my Apple Watch.
I’m feeling really worn out recently, definitely more tired than usual.
I’m just wondering if it’s worth ringing my gp to have them give me a check up or whether they’ll just say it’s a common side effect of hypothyroidism.
Thanks everyone
Speak to GP. When I was off medication for RAI my HR dropped to 39. You could well be very under medicated or something else could be going on which needs looking into.
RedFox23,
A hearts healthy functioning is dependant upon adequate levels of thyroid hormone, particular T3 levels.
You sound as if under-medication could be a possibility. Do you have any recent labs you could post complete with ranges (numbers in brackets) and members will comment.
Yes, you should get your GP to realise that you may need to be referred to a cardiologist.
How much levothyroxine are you currently taking
How long on this dose
Do you always get same brand levothyroxine at each prescription
When were thyroid and vitamin levels last tested
What vitamin supplements are you currently taking
ESSENTIAL to regularly retest vitamin D, folate, ferritin and B12 ……especially before considering TTC
Infertility is common hypothyroid issue unless hypothyroidism is correctly treated
Pregnancy guidelines
thyroiduk.org/having-a-baby-2/
gp-update.co.uk/files/docs/...
Important See pages 7&8
btf-thyroid.org/Handlers/Do...
thyroidpharmacist.com/artic...
Low ferritin, low thyroid levels and miscarriage
Get checked out back your GP for starters. Your thyroid levels may be too low. Or even too high. When I’m over medicated my heart rate drops very low. Once it was in the 30’s. I was taken to hospital. My Levo T4 was over medicated. My TSH was suppressed but my T3 was too low. I am a very poor converter of Levothyroxine T4 to active T3. Once I was finally put on T3 Liothyronine medication my heart rate resolved to now about 58bpm resting on my Nike Apple Watch. I’ve noticed if I’m going over medicated my heart rate drops. The opposite to what you’d think. Your TSH needs to around 1.00 and your T4 and T3 midway. You might need to see an endocrinologist as GP’s often don’t know enough about thyroids.
I’ll ring up next week and book an apt. My latest thyroid blood results seemed okay but I can tell somethings not right. Thank you everyone!
What were your most recent thyroid results
How much levothyroxine are you currently taking
Have you recently had change in brand of levothyroxine
Many people find different brands are not interchangeable
Are you a super fit person if no then definitely should contact your doctor but those HR watches in my opinion are not 100% accurate.
Definitely not super fit! Slim and moderately active but not an athlete by any means! It came to my attention because a nurse mentioned it whilst I was in for a minor procedure recently. She checked it a few times and spoke to the Dr.
Since then I’ve monitored it on my watch - I agree I’m not sure how accurate they are! I think il get checked over anyway just for peace of mind. Thanks for your reply 😊
You might benefit by purchasing a pulse monitor from drug store or Amazon Ive been toying with this as well my pulse goes pretty low (not as low as you) and Im not fit by any stretch but when my pulse goes low I get anxious for some reason.
Hypothyroidism is well known to give a low heart rate, but this usually resolves with treatment. I know from my own experience that there are other conditions that cause low heart rate.
As well as having Hashimoto's, I have a heart condition that causes low heart rate and I have a pacemaker to bring it back to normal. This is quite a serious condition and without the pacemaker, it could be fatal.
I'm not trying to scare you, but it might be a good idea to see your GP and ask for an ECG, just to be on the safe side.
My husband also has a heart condition that results in a usual rate in the low 40's. Occasionally, he'll get down into the 30's. One thing we weren't aware of until recently though, is that a person with a really low heart rate should not be anaesthetized without first being put on a temporary pacemaker, because their rate could go so low that they die! This would apply to IV sedation for dentistry and scopes such as a colonoscopy procedure. You should definitely look into this further, but in the meantime, make sure that you don't have to be sedated without the doctors involved knowing that your heart rate is usually VERY low (it might not be low when they take it themselves though, because you might be stressed about an upcoming procedure).
This is so interesting because it was when I came round from sedation that they noticed my heart rate was unusually low! The nurse checked it 4 times and called in the consultant who looked at me and said it was probably because I exercised now and again 🤔
You'd have to be super-athlete to have a rate that low from exercising, I think.
Heart rate and hypothyroidism 
heart rate after thyroidectomy
Hashimoto’s heart rate increase
Low Heart Rate - Hypothyroidism
