CommunityStacking & Switching

Should I switch from Reta to Zepbound?

17 replies12 peopleJun 18, 2026☆ Follow
Summary

Should I switch from retatrutide to tirzepatide while losing weight?

The original poster has lost 52 pounds so far on retatrutide after initial diet and exercise and is considering switching to tirzepatide. Most replies advise staying on retatrutide because it appears more effective for many, though some note heart-rate increases and suggest splitting doses or adding low-dose tirzepatide to reduce food noise. A few users report better results or fewer side effects on tirzepatide alone and describe successful stacking or switching back. Individual responses vary widely and long-term data are limited.

What this discussion establishesWhere people disagree

Some participants favor staying on retatrutide while others prefer tirzepatide or a combination; a minority switched back to tirzepatide due to heart-rate or glucose concerns.

Still open

Whether the heart-rate increase on retatrutide is clinically significant for healthy users or resolves with time and fitness changes.

Nothing here is advice.

17 replies · 12 people
SteadyCinder47archiveopening postJun 18

Just to give background, I'm a 5'10" guy in my early forties. Started at 290 pounds in mid-February. Diet and exercise alone brought me to 266 when I took my first Reta pen on March 26. Now at 238.

BlueSignal52archiveJun 18

Keep going with Reta until you reach your goal weight, then consider other options for maintenance if you want. No reason to switch when it's working this well. I began at 1 mg from a starting weight of 230 and after 13 weeks I'm at 3 mg weekly and down 37 pounds. I originally planned to stop eventually but I feel good on it and like the results, so I'll probably just lower the dose for maintenance instead of changing drugs.

CopperSignal27archiveJun 18

On average, 12 mg of Reta over a year produces about 29 percent weight loss. Starting from 290 that would bring someone to roughly 202 pounds and a BMI of 29 from 41. Tirzepatide is a bit less effective on average, so if substantial loss is the goal Reta may be preferable. Individual responses differ a lot, and you won't know your own until you've been on it a year at higher doses. If hunger returns before the week ends, dosing every five or six days can help. Depending on cost, Reta may also be cheaper than brand tirzepatide, though the latter avoids risks of mislabeling or contamination.

SlowLantern29archiveJun 18

My experience may not match yours but it might give someone ideas. I began by using a friend's brand-name Zepbound to test it since insurance wouldn't cover me. Knowing we'd both increase doses, I moved to research versions right away and it felt straightforward. The friend still gets brand Zepbound through insurance at the top dose and now adds some Reta I provide. It's worked out as a good arrangement for both.

QuietSignal61archiveJun 19

I wouldn't switch. Reta works better if you have no heart issues. Zepbound tends to cause more fatigue and won't be as strong, plus you can't adjust the dose yourself. If you want tirzepatide just get that directly. You mentioned getting hungrier toward the end of the week, so splitting the dose should fix that. I've dosed every three days from the start and after eight weeks at 2 mg every three days I had to lower it because appetite returned too strongly.

PatientPebble79archiveJun 19

Adding some tirzepatide to the Reta has helped many people who found it reduced food noise.

SlowLantern29archiveJun 19
↳ replying to @QuietSignal61

There are guides online for moving medication from an autoinjector pen into a sterile vial with a Luer-lock syringe. I started the brand version at 1.25 mg and appreciated being able to microdose. I still find tirzepatide useful in a stack for controlling food noise. Different people respond to different approaches.

CopperMeadow83archiveJun 19

If resting heart rate is an issue, consider eloralintide instead of tirzepatide, or combine it with Reta but start very low. Eloralintide tends to lower resting heart rate indirectly. Stage-two cardio or lots of walking has helped me keep my rate the same or slightly lower than before Reta, though being leaner now may also play a role. Eight hours of sleep and fewer sugary or starchy carbs also keep it down. What dose are you currently using?

WryBramble37archiveJun 19

If you can get Zepbound at your copay amount, try it for a month or two and see how it goes. Keep the Reta in the freezer so it stays good. If the Zepbound doesn't work well you can always go back.

CopperSignal27archiveJun 19

From what I recall, the average initial heart-rate increase was around 6 bpm on Reta and 2 bpm on tirzepatide.

SteadyCinder47archiveJun 19
↳ replying to @CopperMeadow83

Thanks. I'm in week two at 7 mg. I don't know much about eloralintide yet but I'll check it out. I'm already on fairly low carbs with almost no sugar, and I lift three or four times a week plus bike one or two times. I could probably spend more time in zone two.

SteadyCinder47archiveJun 19
↳ replying to @CopperSignal27

I think the numbers I saw were 6-8 or 8-10 bpm. My daily resting rate may have dropped a bit, but the rate during sleep has gone up.

SteadyCinder47archiveJun 19
↳ replying to @WryBramble37

I've seen others try that approach. I'm thinking about running 4 or 5 mg of Reta with 1-2 mg of tirzepatide each week to test it. Have you tried the combination yourself, and if so what doses worked for you?

WarmAnchor46archiveJun 19
↳ replying to @QuietSignal61

This is the part that confuses me about comments like that, though it's not your fault. Why does tirzepatide cause fatigue for me while Reta doesn't? Maybe I'm answering myself: Reta shares the same two amino acids as tirzepatide, but the added glucagon component boosts metabolism and heart rate, which might be what overcomes the fatigue. Bill

PatientPebble79archiveJun 20
↳ replying to @SteadyCinder47

I began with tirzepatide in December and stayed at 1.66 mg for five months before adding Reta. Knowing I respond well to low doses, I started Reta at 0.5 mg and went up to 2 mg with no side effects. I'm not chasing rapid loss because that would be too much shock for my body. Slow and steady is better for me, averaging about six pounds a month. Reta helped me break a plateau. I'm mostly off tirzepatide now, though I added 1 mg to my 2 mg Reta dose today for some reason. I'm satisfied with how it's going. What GLP-1s and doses have you used before? That gives a clue where to begin. If you've already been on a high dose you can probably start Reta higher; if it's your first GLP-1, begin low to see how you react. Good luck.

NorthAnchor76archiveJun 21
↳ replying to @SteadyCinder47 (opening post)

I tried both retatrutide and prescription tirzepatide. After a month on retatrutide I switched back because of higher heart rate, more food noise, and elevated fasting blood glucose. Those issues went away once I returned to tirzepatide.

WryHarbour43archiveJun 22

I'm going the opposite direction from you. I started on tirzepatide and have thought about adding Reta during slowdowns but decided to keep things simple and stay with tirzepatide. It sounds like you're doing well on Reta, so I'd fill the Zepbound prescription and just store it or pass it along until you actually need it. There's value in not changing what is working. I see plenty of people here trying lots of different things or getting impatient. I have some Reta in the freezer that I might add later during maintenance or if I stall on tirzepatide, but for now I'll stick with what got me here.

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Should I switch from Reta to Zepbound? · ZyraTrack Community