Increased Resting Heart Rate on Mounjaro

[macandcheeseforthewine]

I know that an increased resting heart rate can be a fairly common side effect on mounjaro.

I monitor my pulse a couple of times a week, and two weeks ago I noticed that my resting heart rate had increased by 15-20 beats per minute. Whilst that might not be a problem for some people, I'm slightly concerned as my usual resting heart rate is already high (right at the top of the range), sitting anywhere between 90-100bpm. With the increase, I'm now sitting at around 100-115bpm, which is outside of the normal range.

I just wondered if anyone else had experienced an increase in resting heart rate, and if so, has it stayed at the higher rate or has it come back down?

I don't have any palpitations etc, I literally wouldn't know it had increased if I hadn't checked it. Nothing else has changed medication wise etc.

I will be contacting my prescriber, just wondered if anyone had experienced anything similar?

Not that high but I also had increased heart rate - I had actually worked hard to bring down before starting mounjaro. After I started it, it increased by about 10bpm to the high 80s. It has settled down now four weeks in and is around 72. Are you monitoring it as an average?

Yes, as an average. My heart rate flits up and down quite wildly. I was thinking about going to the GP about it before I started mounjaro as it was so close to the top of the normal range, but put it off because I thought they'd just fob me off and tell me it's still within the range.

I kind of wish I had gone now though, because I now feel as if I'll be fobbed off by blaming it all on mounjaro and told to stop (which I don't want to do as no other issues and working well). If my resting heart rate hadn't already been high then obviously it wouldn't be such a problem.

It's good to hear yours settled after 4 weeks. I think it's been around 2.5 weeks for me, and I'm actually away next week, so might just wait until I'm back and see if it settles at all before seeking further advice.

Actually, I've just checked it today after posting the above, and it seems to have gone back down to under 100 (high 90s). Will keep an eye on it and hopefully it will remain there.

I think anything over 85 is a v high resting heart rate and anything over 90 is very worrying. Over 100 is dangerous.

Resting heart rate should be around 60 to 70.

I'd pop to the doctor if I was you. I don't want to scare you but if your heart rate doesn't get back under 80 soon you r at risk for lots of complications.

Yes, my first 2 weeks on the jabs my heart rate went up by several beats, but by week 3 things had settled down to my pre MJ rate.

The NHS state that a normal resting heart rate is anywhere between 60-100bpm. As do pretty much all other medical websites when you Google it.

That's the main reason I haven't been to the GP even before I started mounjaro, as whilst high in the mid 90s, it still falls within the normal range.

I am away this week at somewhere where I actually needed to have a nurse check me over at the start of the week (physio rehab place) so had quite a long chat about it. My blood pressure and pulse were checked (everyone's is, not just me!). My pulse definitely seems to have settled again to mid 90s.

I'm not happy about it. It used to be high 80s, then seemed to go up permanently after having covid twice and emergency surgery in late 2023. But given it's still within what the NHS class as normal range (and my experience with my thyroid blood tests show that the NHS are obsessed with being in the normal range for those and couldn't care less if you are still symptomatic) I am perhaps understandably cautious about trying to get a GP appointment only to be told it's a waste of time.

Can I please ask what the outcome of this was. I’m in the exact same position currently

So, I did eventually go to the GP, as my heart rate hadn't gone down. They did an ECG, which was normal. Had a load of blood tests ordered.

My results came back, and a few were off - thyroid (expected, as I have underactive thyroid and am on T3 medication), CRP raised at 14, and high ferritin (which could be due to inflammation as per the CRP result).

I had to get a telephone appointment to discuss the results, and it was a different GP to the one I had the original appointment with. They chose to blame my thyroid meds (even though it isn't those and I had a long discussion with the original GP about that as I monitor my pulse regularly due to the type of meds I'm on). I was then told to contact my endocrinologist.

So, less than helpful really.

I’m sorry they were useless. How are you feeling now? Has it sorted itself out?

Nope, still high.

I'm in a difficult situation really. If I go to my endocrinologist he'll focus on my high heart rate and say I'm over medicated on my thyroid meds. I'm not, but unfortunately the med I'm on is hard to get prescribed on the NHS, and I really don't want to run the risk of my prescription being reduced. Ironically, it's only because I'm on this medication that I monitor my heart rate in the first place (and how I know it's nothing to do with the thyroid meds and everything to do with the Mounjaro).

I guess I was hoping that the GP would do something like prescribe a beta blocker for a short while to see if it helped.

I'm also very nearly at target weight, so going to start coming down the doses to try and find a sweet spot for maintenance. I'm hoping that might help (but given I was only at the 5mg dose when my heart rate increased I'm not holding out that much hope).

Try a lower dose. I used a private clinic which supports micro dosing. I started on half the 2.5ml dose. Just count the clicks, I think it's 60 for the full dose and reduce it by half. I have lost 2 stone gradually this way. I have increased the dose slightly now, but still only taking 1.8 mls a week. I have a 5ml pen and do 23 clicks. It just makes me able to stick to a healty diet without trying. I guess the manufacturers won’t recomend it as it means your pen lasts longer and you don’t spend as much. It also means you don’t suffer any side effects.