Semaglutide titration and resting heart rate, anyone else tracking this?

Posted by labrat_hank in Weight Loss & Metabolic - 8 points, 4 comments.

I have been on semaglutide for about 10 weeks now, slowly going up from 0.25 to 0.5mg weekly. The appetite suppression is real for me, no question about that. But the thing I did not expect was how much my resting heart rate shifted.

Before I started, my RHR sat around 58-62 most nights. After about week 3 it climbed to 68-72 and has stayed there. My HRV dropped maybe 10ms on average too. I wear a Garmin constantly so I have decent baseline data to compare against. Could be stress, could be sleep quality changing because of the GI side effects, but the timing lines up suspiciously well?

I read that GLP-1 agonists can affect heart rate through the autonomic nervous system but I have not seen much discussion of it in the community here. Everyone talks about nausea and appetite but nobody mentions the cardiovascular numbers.

My fasting glucose came down from around 5.3 to 4.8 mmol/L which seems like a reasonable shift. Lipids I will check again next month.

For those of you further along, did the heart rate thing settle eventually or is it just the new normal while on it? Curious if anyone has bloodwork trends they want to compare.

Comments

• tiredmegan: For what it is worth I noticed the exact same thing on my Garmin, RHR went up about 8-10 bpm and HRV took a dive. Class data to have but also mildly unsettling when your watch keeps telling you you are stressed. Mine did settle a bit around week 12-ish, came down maybe 3-4 bpm but never went fully back to baseline. Still higher than before. Could be the GI stuff wrecking sleep for the first while, could just be the drug doing its thing with the autonomic nervous system. The real question thoug
• labrat_hank: Good to hear yours settled a bit around week 12. I am at week 10 now so maybe I have a couple more weeks before it trends down. Did yours drop gradually or just one week it was lower and stayed there? On the eating question, that is a fair point. I am probably under-eating honestly. Some days I realise it is 4pm and I had maybe 800 calories. I track food but not consistently enough to call it proper data. Could be part of the HRV drop too if my body is just running on fumes. I will pay more att
• fasted_scientist: Ngl I reckon the food intake thing is a massive factor. If you are barely eating, your body is going to be under a lot of physiological stress. I saw something similar with my own bloods when I was cutting hard. It is worth checking if you are getting enough electrolytes too. That might explain the heart rate jump better than just the drug itself.
• labrat_hank: The electrolyte angle is a good call actually, I had not thought about that properly. My intake has dropped quite a bit, probably around 1400-1600 kcal on most days, so the stress angle you mentioned fits. I do salt my food pretty heavily but I have not been tracking potassium or magnesium at all. Could be something there. Did you supplement electrolytes when you were cutting, or just adjust food?

Community discussion - research and educational context only. Not medical advice.