I have a under active thyroid does it make your heart go faster?

[kissmelittleass]

I've just finished two courses of antibiotics for a chest infection plus three days of steroids, two different doctors plus doctor at A&e said my heart was fast.
I've felt like this for months, having a holten monitor and bloods this week as thyroid hasn't been tested for near 18 months.
I said to the doctor could it be my thyroid causing fast heart rate as it's under active and I'm on 50mg eltroxin since I was diagnosed in 2017, she said no a fast heart rate would usually be seen in over active thyroid patients.
My mum said this is wrong?asshe had a very fast heart beat with a under active thyroid whilst on medication and her meds needed adjusting so I'm wondering if any of you have had this?

The Dr is right. My heart only ever went fast when a blood test showed I was over treated and they had to reduce my thyroxine.
When they adjusted your mums meds are you saying they put them up?

@Everythingiswonderful Hi yes the doctor told her the dose she was on was too high after a blood test and adjusted her thyroxine meds to a lower dose and everything settled down for her after that.
My mums again just recently changed from 100mg down to 50 mg, hers is often adjusted where as I've been consistently on 50mg since I started on Eltroxin in 2017.

Usually with hypothyroidism, your heart would only go fast if you were on too much thyroxine. Your dose is actually quite low, but it may still be a bit high for you. Really, your thyroid bloods should be done every year, so it would be good to see your GP and arrange a blood test and possible review of your dose.

I wear a Fitbit and the first I know that I am coming down with a cold is my resting heart rate shoots up. Then a day or two later I get the normal symptoms of sore throat, runny nose etc. It may just be being ill that has pushed your heart rate up, maybe wait till you are fully recovered and see how it is then.
For what it’s worth I am on thyroxine and didn’t see any change in resting heart rate after starting on it.

I developed a fast and irregular heart beat after a chest infection. See your GP

Thanks everyone!
@lotsofdogshere hi as three doctors have mentioned the fast heart rate over the last week I actually spoke to one of the doctor on the phone and she has arranged for me to have a 24 hr holten monitor on Thursday and bloods for thyroid and iron on Friday.
Can I ask what happened after your chest infection with your heart rate? Were you given any treatment or did it calm down? TIA

@kissmelittleass your mum was over treated as her dose was too high so she was being pushed, sort of, into being over active rather than underactive that was why she had a fast heart rate.
You have had a long time without a blood test, it’s usually at least an annual blood test to check the dose doesn’t need adjusting.

X post!
Glad you are having a blood test

@Everythingiswonderful Thanks! Makes sense what you're saying regarding my mums heart rate.
I tried to get a blood test for my thyroid when the 12 months were up but it was like talking to a brick wall I was told to wait a few months! Getting it done on Friday at last after nearly 18 months !!

Hello kiss - sadly the atrial fibrillation (aka irregular heart beat ) remained. It was a grim chest infection, 5 weeks, 3 lots of antibiotics. I was prescribed blood thinners because the AF means blood clots more likely. This us six years ago, I’m fine. I’m much older than you, 72 - but I can still enjoy a 4 mike walk and other than finding hills more of a challenge, I’m fine.

Here’s hoping you get yours sorted. My thyroid was checked - it’s ok. Best of x

@lotsofdogshere Thanks for replying, glad yours hadn't caused you any problems and that you can live a active life. X

Hi OP. I have Hashi's and a fast heartbeat, sometimes irregular and missing heartbeats. You will find quite a number of people who are properly medicated do too. From what I have read it's because Hashi's goes from being mostly hypo to periods of being hyper as the thyroid degenerates.
Though it could also be caused by other additional health conditions.
I find it very unpleasant, especially if it happens at night time.

@whysorude Great to know, thank you! Last night I could feel my heart racing as I was trying to sleep and had quite a few thumps in the chest ( must be the ectopic beats that was seen on my holten monitor) I felt a bit scared so I'm sat up and came on Mumsnet for an hour!!
Doctors hush hush the thyroid connection at least my doctors do telling me my heart would only race if I had a overactive thyroid but from what I've read on various threads it happens with under active thyroid as well!!
My heart gets up to 138 or a little over at just walking around the house doing things like putting dishes away or loading washing machine but doctor wasn't bothered so I pressure it's fine ( this has recently been seen on the 24 hour holten monitor).