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Tirzepatide 10 to 12.5mg jump, resting HR spiked but HRV tanked

Posted by greg_codes in Weight Loss & Metabolic - 10 points, 4 comments.

Been on tirzepatide for about 7 months now, worked up from 2.5mg slowly. Went from 10mg to 12.5mg two weeks ago and something weird happened with my metrics.

My resting HR jumped from about 58 to 67 over the first 4 days. HRV dropped from mid-40s to like 28. Felt a bit rubbish too, more than the usual nausea. Sleep score on my watch went from consistent 80s down to low 60s.

Ngl i wasn't expecting that at 12.5mg because 10mg was sweet as, barely any sides by that point. Could just be a stress response from the dose change? Or maybe dehydration because the nausea came back a bit and i was drinking less water than usual.

My fasting glucose actually improved though, came down from 5.1 to 4.7 mmol/L. So metabolically something is working better even though my recovery metrics look rough.

Has anyone else tracked HRV through a titration step and seen a dip like this? Curious whether it settles back out after a couple weeks or if it's worth backing down to 10mg. The weight loss has been solid but i don't love seeing my recovery numbers in the gutter.

Comments

  • fasted_scientist: The dehydration angle is probably your best bet tbh. GLP-1/GIP agonists slow gastric emptying and that nausea coming back means you're likely drinking less without realising, which alone would push resting HR up and tank HRV. I'd sort fluids out first before assuming the dose itself is the problem. Have you got any actual data on your intake over those days? Reckon most people guess and get it wrong (myself included). Could try tracking it properly for a few days at 12.5mg and see if the number
  • sleep_coastal: Fasted_scientist is right on the hydration angle. Anecdotally when I went up on tirz I had the same thing, HR up about 8 bpm, HRV cut almost in half. Turned out I was barely drinking because everything made me slightly nauseous. Tracked intake for a few days and I was at like 40oz when I thought I was doing fine. Fixed that and the numbers drifted back within a week. Start there before blaming the dose.
  • greg_codes: Yeah that tracks pretty close to what i'm seeing, the 8 bpm jump and halved HRV is basically my pattern too. Didn't even think about tracking actual fluid intake, just assumed i was fine because i wasn't thirsty. Keen to try logging it properly for a few days and see where i'm actually at. Did you just force water or add electrolytes too? Wondering if plain water is enough or if sodium matters here given the nausea was messing with my intake.
  • greg_codes: Yeah nah i didn't track fluid intake at all over those days, you're right that i'm just guessing. Ngl that's a pretty obvious gap in my data. Started logging it properly yesterday and pushing electrolytes too. Already noticing the nausea eases off when i actually stay on top of fluids. Resting HR came down to 63 this morning so maybe you're onto something. 5mg and see if HRV climbs back up before blaming the dose.

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