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Moving to Reta

12 replies9 peopleOct 18, 2026☆ Follow
Summary

How to switch from tirzepatide to retatrutide without running two GLP agonists at the same time, including what starting dose to use

The original poster has been on 15 mg tirzepatide for nearly two years with steady but slow loss and wants to move to retatrutide alone. Most replies advise starting retatrutide at 2 mg while still on tirzepatide, then gradually lowering the tirzepatide dose or adding other peptides like cagrilintide or semaglutide for appetite control. Several users report successful long-term stacking of tirzepatide and retatrutide with slow titration and no major issues. One user shares a split dosing schedule that produced 1.2 lb weekly loss at low doses of both.

What this discussion establishes

Nothing here is advice.

12 replies · 9 people
ClearFenwick64archiveopening post10h

Hello everyone. I've been on tirzepatide for almost two years at 15 mg. No side effects and no appetite suppression, yet I still have 7 pounds left to lose. My average loss has been 0.6 pounds a week, slow but consistent. I want to switch to retatrutide but don't want to run two GLP agonists together, so what starting dose should I use, 2 mg or higher? Any advice?

GreyLantern71archive10h

Do you already have the retatrutide on hand? I'm on tirzepatide and recently started adding 0.25 mg of cagrilintide for appetite suppression. Just an idea. It seems to be working so far.

SteadySparrow75archive10h
↳ replying to @ClearFenwick64 (opening post)

I might join those voices suggesting to keep the first one going for now as the newer option gets started. Trying two milligrams at the outset seems reasonable to check the effects before changing anything else. Should the plan involve dropping the original compound entirely then lowering it by one or two milligrams gradually while raising the newer dose could work out. Best of luck!

ClearFenwick64archive10h
↳ replying to @GreyLantern71

Yep I've got loads of both retatrutide and cagrilintide. Tried cagrilintide twice at a low dose but it didn't seem to do anything so I forgot about it, may try again.

SteadySparrow75archive10h
↳ replying to @GreyLantern71

Sema turns out quite effective at overcoming weight loss stalls plus it costs less too. A few weeks back I began including some sema and side effects have been almost nonexistent. My guess is that my body has adapted to these GLP types already from having taken tirz and reta before.

IronBramble31archive10h

For more than twelve months now I've combined the two without running into problems. Like other things I've tried I looked into adding one in small steps while cutting back on the first.

GreyLantern71archive10h
↳ replying to @SteadySparrow75

Semaglutide will definitely be in my next order. Want to have this on hand for the future.

SteadySparrow75archive10h
↳ replying to @GreyLantern71

Found semaglutide through a sponsored seller on the forum because the kits came in five milligram sizes and the cost was still low. Started at a quarter milligram level and it worked well to quiet the hunger signals. Also have some cagrilintide on hand yet feel positive about testing this one.

BrightSparrow36archive10h

A single tap option to send stack with the laughing face emoji would be perfect. Comments in the discussion are top notch.

IronKettle95archive9h

Following what others suggested, I stuck with the same amount of Tirz. Then a couple days prior to my Tirz injection I began with 2mg of Reta. Once four weeks passed, if I felt I needed stronger effects I increased the Reta dose to 4mg while keeping Tirz steady. After that point I tweaked one or the other depending on how things went. Since there were just seven pounds remaining I expected to reach maintenance phase pretty quickly.

GreyFenwick31archive9h

My injections happen on Monday evenings for one and Friday mornings for the other. That timing leaves four days in between. Both amounts stay quite modest because I aim for gradual weight reduction in hopes of keeping my muscle. This approach yields roughly 1.2 pounds lost weekly on average.

PlainAlder11archive8h

I have nothing to say about it. Everything here is too complex for my simple thinking. I'm finished with this subject.

IronAlder10archive8h

I wondered if trying one more peptide might help. Something along those lines could work since the target is almost reached and the remaining pounds feel stubborn.

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