CommunityCompound Experiences

Tirz experience = Reta experience?

51 replies23 peopleAug 8, 2026☆ Follow
Summary

Does having no side effects on tirzepatide mean you'll likely have none on retatrutide or the reverse?

Forum users share mixed personal stories when moving between tirz and reta. Several report smooth switches or stacking with little trouble, while others note reta brings extra heart-rate elevation, skin sensations, or different GI effects compared with tirz. Sema is repeatedly described as harsher on the stomach and overall malaise than either of the other two. Transition methods, starting doses, and individual tolerance vary widely.

What this discussion establishesWhere people disagree

Whether absence of sides on one compound is a reliable predictor for the other

Still open

Optimal way to transition doses without setbacks or loss of appetite control

Nothing here is advice.

51 replies · 23 people · page 1 of 2
AmberCinder18archiveopening postAug 8

I'm wondering about a pattern I've noticed in reports, though it might just be stories. Folks mention having no issues with one of these meds and then switching or adding the other without problems either. Obviously individuals vary, but does lack of bad reactions to one suggest you'll handle the second okay too?

LevelThistle44archiveAug 8

I get little or no sides from tirz or reta, yet sema feels stronger. If you handled tirz fine, reta should probably be okay. Going the other direction sometimes brings more bumps depending on how you bridge the doses.

AmberCinder18archiveAug 8
↳ replying to @LevelThistle44

Sema carries a heavier side-effect profile, which is why plenty of people avoid it altogether.

LevelThistle44archiveAug 8
↳ replying to @AmberCinder18

Even at 18-20 mg reta I was surprised how strong 0.25 mg sema felt. I still like it but with plenty of everything on hand I might move to tirz or an amylin agonist once I fine-tune my reta dose between my first and second goal weights. I want easier sleep and a lower resting heart rate. Started at 282 lb, first goal 200 lb, second around 180 lb, now at 200 lb after 34 weeks. I still want to lose the last 20 lb steadily while keeping roughly the same weekly loss rate.

SlowFenwick79archiveAug 8

I've only used brand-name tirz and reta. The sides differ between them. Tirz sides match what you'd expect from brand M. Reta dropped my already low blood pressure further and left me feeling lousy. Couldn't stay on it. Also hunting for that ghk-cu thread if anyone has a link. Still lurking to see if after a few years I've moved past newbie status here—still a newbie.

SlowTimber22archiveAug 8

Go ahead and open that reta you've got tucked in the freezer.

AmberCinder18archiveAug 8
↳ replying to @SlowTimber22

I will eventually, no rush. Meanwhile I've been reading and results are all over the place—some switch smoothly, others get hit hard—so I'm really interested in experiences here, but hardly anyone has shared yet. Back to more reading.

SlowTimber22archiveAug 9

It's a much different crowd here than it was six months ago.

CopperSignal27archiveAug 9

From my own use and from what I've read about receptor activity, reta and tirz produce fairly similar sides. The main difference is reta boosts sympathetic activity more, which can raise heart rate and sometimes cause insomnia. Reta has weaker GIP action than tirz, so GI sides can be a bit worse since GIP helps offset GLP-1 effects, though the gap isn't huge. Reta also seems to trigger more skin sensory issues than sema or tirz, with no clear reason yet. Sema causes more GI trouble than either because it lacks GIP. It can also bring stronger food aversion and malaise. Skin sensory problems are possible but only at very high doses. I had bad nausea, malaise, and food aversion even at low doses of prescribed sema for a year before trying grey peptides, but a

RustKettle57archiveAug 9

I used 2.5 mg tirz for a month about a year ago before I had done much research. I was still eating poorly and not drinking enough water. It gave me the worst heartburn I've ever had; nothing helped and it lingered weeks after I stopped. I'm sure the diet and dehydration were the real cause. This year I started reta and had no trouble until I rushed up to 7 mg. That brought unpleasant skin sensations that lasted a few weeks. I'm still at 7 mg and added 2.5 mg tirz three weeks ago for better appetite control, which worked well. Besides the skin issue, which has passed, I've had no real negatives from either drug this time and have lost 45 lb, which I'm thrilled about.

SteadySparrow75archiveAug 9

I was doing 5 mg tirz twice a week on Friday and Monday. I added 2 mg reta split across Friday night and Saturday morning. After seeing few sides from the reta I decided to be bold and took 6 mg tirz on Monday. It felt like I'd taken 10 mg—the GI symptoms hit hard. I was worried about the reta but the tirz was what got me. I'll still inch reta up to 4 mg soon, but I'm more cautious now because reta can bite harder than tirz.

ClearLedger33archiveAug 9
↳ replying to @LevelThistle44

Yeah, me too. On Sema I felt like death was coming fast. It turned out the real physician who wrote the prescription, unlike some wellness spot, put me straight onto the top amount right away. A couple years on, after checking other choices, I realized that doctor either meant harm, lacked basic knowledge, or figured my size justified the maximum level from day one. My take might be off, but Tirz and Reta gave me basically no reactions at all, and I'd take any other pain over repeating how the opening Sema dose felt.

LevelThistle44archiveAug 9
↳ replying to @ClearLedger33

Wow, our experiences sound very different. I had the worst sides when I started sema compared with the minimal ones on reta or tirz—malaise, stomach discomfort, appetite crushed. Dropping from 0.25 mg to 0.125 mg split doses mostly fixed it. Starting at 2.4 mg must have been rough. How did your weight change during that time?

WarmSparrow60archiveAug 9
↳ replying to @RustBramble70

At first things felt negative yet should improve with time. Because of ongoing worries that the blended medication might vanish people from the other discussion board rushed over here hunting for different choices. It is just typical behavior including my own back in autumn twenty twenty five. Fresh members began posting right after signing up repeating the same silly queries they posted elsewhere. In time I figure folks will settle into this setup or return to their old spot ending up mixed in with everyone else like being locked down. I spot the signs when someone new is about to blow up their own account. Often staying quiet works best just looking ahead taking in the details and pulling it all together.

IronLedger99archiveAug 9
↳ replying to @AmberCinder18 (opening post)

On tirz I had zero sides. When I added reta on Friday I felt a bit drained yesterday but today I'm feeling great. It's still early, but with how my body usually works I'm pretty sure the worst is over. I'll keep the mix for the last 27 lb to reach my goal of 145 lb, using two days on, two days off for each.

PatientHarbour61archiveAug 9
↳ replying to @PatientPebble79

If you're in the trials or the expanded access program and getting it from Lilly, that would count as brand name. The drug itself still doesn't have a brand name yet though.

PatientAlder89archiveAug 9
↳ replying to @ClearLedger33

Sure you were nervous about starting others after how bad that must have been. Glad it didn't put you off trying anything at all.

PatientHarbour28archiveAug 9
↳ replying to @PatientPebble79

I'm so stuck on the new name part I can't focus on the side effects. Can't decide—should brand reta be called Xyzolvify or Jentamub?

PatientPebble79archiveAug 9
↳ replying to @PatientHarbour28

Maybe they'll run a contest. I saw some possible names Lilly was floating but as far as I know they haven't picked one yet.

GreyFenwick31archiveAug 10
↳ replying to @SlowFenwick79

Interesting—I'm usually lowish on BP, like 100-110 over 60. I wonder if reta would push it lower; never heard of that happening.

LevelThistle44archiveAug 10
↳ replying to @GreyFenwick31

GLP-1 drugs and weight loss in general usually lower blood pressure.

GreyFenwick31archiveAug 10
↳ replying to @LevelThistle44

Thanks, I'll keep an eye on it. I figured the drop came from the weight loss itself, which comes from the medicine, but I didn't realize the medicine could lower BP directly.

IronKettle95archiveAug 10

Those accounts got placed on my blocked users section.

PatientPebble79archiveAug 10
↳ replying to @AmberCinder18 (opening post)

Me neither, but my normally low BP has dropped further the past few weeks and it's a real drag. Going to skip reta this week and see if it improves.

PatientHarbour61archiveAug 10
↳ replying to @GreyFenwick31

I'd probably avoid reta with BP that low. It could cause symptomatic hypotension, at least orthostatic. Your BP probably won't fall much more because your body will raise heart rate to compensate, so expect a bigger heart-rate jump instead.

GreyFenwick31archiveAug 10
↳ replying to @PatientHarbour61

Got me thinking. The prior week while on Tirz my heart rate at rest felt higher than usual hitting around seventy when it normally sits lower between fifty five and sixty five. After looking at the discussion yesterday I measured my blood pressure coming in at ninety nine over sixty. I asked my husband to check his as well because he takes the top amount of his blood pressure medication and his came back at one hundred six over seventy. I said to him that we should watch it closely since he could possibly need to reduce his medication level along with the Tirz and dropping weight.

GreyFenwick31archiveAug 10
↳ replying to @PatientPebble79

Oh wow—when you say bottomed out, did you feel it? What tipped you off that it was low?

LevelThistle44archiveAug 10
↳ replying to @GreyFenwick31

My most common symptom is head rushes when standing up fast. My reading isn't especially low, but these rushes have been far more frequent over the last eight months than before.

IronKettle95archiveAug 10
↳ replying to @GreyFenwick31

I own a wireless blood pressure monitor that connects straight to my phone app. Each day I check my readings and they get stored automatically, producing visual charts I can look over. Numbers have always appealed to me. My readings used to run a little high even on a low dose of medication. These days I'm off everything and the values sit mostly where they should. The same device also records my pulse. Because I'm on this treatment I wanted to watch the actual figure instead of guessing about it. That pulse value hasn't shifted at all.

PatientMeadow16archiveAug 10

I don't think it's fair to compare my tirz and reta experiences directly. I started tirz from a compound pharmacy and went up every four weeks: 2.2 mg, 4.4 mg, 6.5 mg, then 8.8 mg for a few weeks. My body didn't like 8.8 mg—very tired the next day, constant heartburn of varying intensity, no appetite, and my wife said I was grumpier than usual. I also burped constantly on tirz, some with nasty aftertaste. I switched to reta mainly because what I'd read seemed to fit my goals better. Started reta slow at 1 mg and titrated over three months to 3 mg. Only felt a little sweaty at times at 3 mg. I was able to stop tirz completely during that period. I miss tirz because my knees benefited most from the inflammation reduction; they started hurting again on reta without it. I'm now stacking both and looking into wolverine protocol with KPV coming soon. Knees feel better and the scale is still moving.

PatientPebble79archiveAug 10
↳ replying to @GreyFenwick31

My symptoms were present but unnoticed until the neurologist visit for my POTS follow-up. Readings are always checked in multiple positions there. The device failed to register properly, leading to manual checks repeated because the value was so low. Tracking at home showed the systolic number stuck in the seventies. Adjustments to my medications continued without much change, leaving me at 75/48 and pulse 96. Symptoms had become prominent then. Being upright was difficult with dizziness, vision narrowing, and stomach upset. My balance felt off, so I searched for things to hold. Electrolytes and liquids are being increased now, along with a few drugs, yet little headway appears. Therefore the injections will be paused next to observe any difference. Not much information turned up on them reducing pressure, but every possible contributor is worth examining. Appreciate the inquiry!

CopperSignal15archiveAug 15

This question interests me as well. Sema caused me no problems at all, so I went up to the highest amount before trying a moderate level of tirz without any issues either. For the past year and a half I've stayed at 15mg of tirz and now I'd like to try reta instead because I still need to drop another 30 pounds after already shedding 78. New side effects concern me somewhat, yet my bigger fear is that reta might not affect me at all. Over nearly two and a half years the first drug took off 50 pounds while the second removed 28, and although I know progress happens gradually and I'm fine with that pace, I really don't want things to drag even more. My idea was to stop tirz suddenly and begin with 2mg of reta, but the possibility that it does nothing and I put weight back on has me anxious.

PatientHarbour61archiveAug 16
↳ replying to @CopperSignal15

Switching abruptly from a high amount of the first medication straight into the lowest starting level of the second one feels really inefficient. It ends up working about like dropping the original down to its beginner amount. Months can pass with low effectiveness and probable weight gain before higher levels around nine to twelve milligrams start to help, and even then plenty of folks still report feeling off even after their plateau breaks. I have not tried the first medication myself, yet the easiest shifts I have noticed involve slowly reducing it while raising the second one at the same time. Holding the total around one full dose tends to create the fewest problems during the change.

LevelThistle44archiveAug 16
↳ replying to @CopperSignal15

My dose jumped from five milligrams of Tirz up to sixteen milligrams of Reta across fewer than fourteen weeks, and reactions stayed minimal. The highest amount reached twenty milligrams each week. Since beginning the switch on 1/10 my weight has fallen by seventy three pounds for a total loss of eighty three, leaving roughly twenty more to drop. I split everything into lots of tiny injections while checking reactions during each increase. That approach ensured any overshoot would let unwanted effects fade quickly. An earlier thread covers additional information.

SlowFenwick79archiveAug 16
↳ replying to @PatientPebble79

I figured my earlier reference was already obvious enough. Still, it looks like I have to spell out that I was talking about the official version of the first substance plus the unofficial copies of both that one and the other compound.

SlowFenwick79archiveAug 16
↳ replying to @GreyFenwick31

My usual pressure hovers around ninety over sixty. During that period it measured eighty over forty whenever things felt fine. I skipped any checks on days with symptoms, so the lowest point stayed unknown. Being new to the whole thing and noting the fifteen minute wait.

AmberSignal47archiveAug 16
↳ replying to @SlowFenwick79

The punctuation mark placed right after that word and ahead of the two abbreviations created a grouping effect. That made the product identifier apply to the pair instead. My goal isn't nitpicking but rather pointing out the origin of the mix-up. While this isn't a major issue here, precision often counts when handling injections. Everything checks out now.

SlowFenwick79archiveAug 16
↳ replying to @AmberSignal47

Another case where skipping the serial comma led to mix-ups.

KeenKettle50archiveAug 16

Zepbound 12.5 mg was a wild ride for me. Every time I ate complex carbs like rice, pasta, or bread I got impossibly strong drowsiness.

LevelBeacon74archiveAug 16
↳ replying to @LevelThistle44

And for some folks BP meds as well, yeah.

AmberSignal47archiveAug 16
↳ replying to @SlowFenwick79

Hilarious! I didn't realize you meant three different substances. I thought you'd just unnecessarily used the comma at all when describing just two. Yes, the Oxford comma would have bailed that out. Good one.

SlowFenwick79archiveAug 16
↳ replying to @PatientPebble79

At the time I used the initial version, the later one had yet to be thought of.

SteadyAnchor13archiveAug 16
↳ replying to @GreyFenwick31

My pressure readings are about the same, and that product left them unchanged. All it did was speed up my heartbeat.

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