Weight jump after switching from Mounjaro to QYC tirzepatide — looking for advice

GalloB73

GalloB73

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Hi all,

I'm not really alarmed by this, but since my weight has stayed within roughly 1lb for the last year, I figured I'd check whether anyone here has seen the same pattern and could share some insight.

I've recently moved to grey market tirzepatide (QYC). Maintenance has been my mode for more than a year now, with a target range of 59-61kg (130-134lbs).

For over a year my weekly dose has been 3.8mg (previously via prescribed Mounjaro pens).

My first batch came through a reseller, back when I was still figuring things out. I was told the product was QYC, and QYC confirmed this. They provided their vendor Janoshik COA, which listed the average fill for this batch as 30.46mg across two vials (31.81/29.11). I used 3.2ml of vendor BAC to reconstitute, then filtered into a sterile vial, all with aseptic technique. So far I've taken 0.4ml twice (3.75mg), yet my weight has jumped by 2.45kg (5.4lbs) compared with my lowest point the week before Christmas (so over 4 weeks).

With my first dose I had very strong suppression plus some mild stomach pain, which made me wonder if the vial was overfilled, so I split the second dose to see if that would help — and it did. I simply wasn't expecting the scale to go up for a second week running.

The table below lays it out more clearly:



Date5 Nov12 Nov19 Nov26 Nov03 Dec10 Dec17 Dec24 Dec31 Dec7 Jan14 JanWeight59.258.358.4/57.95/57.10//59.0059.55dose3.8mg MJ3.8mg MJ3.8 MJ​

3.8mg MJ3.8mg MJ3.8mg MJ3.8mg MJ3.8mg MJ​

3.75mg QYC3.75mg QYC3.75mg QYC​

FLUFLU​

Strong suppression day 2 some stomach painSplit dose 3mg day 1

0.75mg day 5

I suspect I'm overthinking this, since it's my first time with grey and I'm terrified of regaining weight after being obese for most of my life. I know 100% I will be a life long GLP1er. I've since placed another order for JEEP tirzepatide, which is in storage, and my batch has quite a lot of vendor and 3p testing. I've also got a few bottles of Hospira BAC arriving in about 10 days.

I'm watching my food very closely now, but aside from Christmas week, when I did eat more than usual, nothing has really changed. I'm still lifting 3x a week, yet this is the first time I've seen such a rapid gain in such a short period. Is this normal when transitioning to grey? I keep telling myself there's no way I could have eaten the calories required for it to be fat. Even on Christmas day I only managed one meal, though it was comparatively big by my standards.

I've been below my lower weight target for a few weeks anyway, and I'm now actually within my range, so it's not really a big deal as long as it doesn't continue creeping up. If any of you have been obese and lost in the past you will know that awful feeling of dread when you see a gain on the scale, but I'm trying to see it in the wider context so I don't freak out.

My question is, do I give it 4 doses and assess at week 5, and if I'm still gaining, should I switch to my JEEP vials and Hospira?

Or do I just need to crack on and adjust the dose of my QYC vials and watch my diet for a few more weeks and see if I stabilise again?

I did get very strong suppression from my first dose, more so than what I was previously getting from Mounjaro so I don't think it's lack of GLP1. Maybe as I was ill with the flu before Christmas that's what contributed to my weight dropping and as I've skipped a few weeks weighing in, and had the festivities and fancy food I haven't noticed it creep up over Christmas? I'm just looking for a bit of reassurance really I don't want to have a knee jerk reaction if it's normal to expect a bit of fluctuation in the first month.

My reseller tirz was very expensive so I will be pissed if I can't use the other 9 vials!

Any advice gratefully received.
 
If that initial QYC tirz dose hit you with powerful appetite suppression, then the product probably isn’t fake. It seems like you’re already doing what’s needed to keep an eye on what you eat. For my part, I wouldn’t stress about it too much. Maybe try tracking both your food and water for 2 weeks, then check what the results look like.
 
Given that you've been unwell, plus what others have said, I'd suggest sticking with it for another 2 weeks while logging your food, then reassess. For more than a year I've weighed myself every day to follow my progress, and it still surprises me how much the number fluctuates from one day to the next. When I keep my eating on track, record what I consume, and stay active, the bigger picture has moved in the right direction. Many factors can influence weight over a short window. Best of luck, and don't give up.
 
PopTart said:

If that initial QYC tirz dose hit you with powerful appetite suppression, then the product probably isn’t fake. It seems like you’re already doing what’s needed to keep an eye on what you eat. For my part, I wouldn’t stress about it too much. Maybe try tracking both your food and water for 2 weeks, then check what the results look like.
Click to expand...
Thanks, that's genuinely useful.
 
Grey is the only option I've used. It does the job. When it doesn't, an under fill could be the reason. Or... the festive season might be playing a part🙂 still, @testyonenow42 makes a fair point: weight goes up and down. So long as the end result is progress🙂
 
byefatlicia said:

Grey is the only option I've used. It does the job. When it doesn't, an under fill could be the reason. Or... the festive season might be playing a part🙂 still, @testyonenow42 makes a fair point: weight goes up and down. So long as the end result is progress🙂
Click to expand...
You're right — I should be looking at the longer trend instead of fixating on just the past few weeks. Thanks.
 
testyonenow42 said:

Given that you've been unwell, plus what others have said, I'd suggest sticking with it for another 2 weeks while logging your food, then reassess. For more than a year I've weighed myself every day to follow my progress, and it still surprises me how much the number fluctuates from one day to the next. When I keep my eating on track, record what I consume, and stay active, the bigger picture has moved in the right direction. Many factors can influence weight over a short window. Best of luck, and don't give up.
Click to expand...
That’s helpful to hear, thanks. My weight had been basically stuck for more than 6 months, so this morning I likely overreacted—maybe some leftover anxiety from all the loss/gain cycles I’ve gone through before.
 
Hi,

When I came down with the flu previously, I dropped 4-5 pounds over the course of a few days. I'm fairly confident the decongestant I was on acted as a diuretic in some way (the first night after taking it, I was up multiple times to urinate). Once the flu passed, those 4-5 pounds came back.

Given both the flu and whatever medication you've been taking, my guess is that this is simply water weight shifting around. The fact that you held steady for such a long period right before getting sick also suggests that the lower number was the outlier, rather than where you are now.

Let us know how it goes!
 
wiggle_zoom said:

Hi,

When I came down with the flu previously, I dropped 4-5 pounds over the course of a few days. I'm fairly confident the decongestant I was on acted as a diuretic in some way (the first night after taking it, I was up multiple times to urinate). Once the flu passed, those 4-5 pounds came back.

Given both the flu and whatever medication you've been taking, my guess is that this is simply water weight shifting around. The fact that you held steady for such a long period right before getting sick also suggests that the lower number was the outlier, rather than where you are now.

Let us know how it goes!
Click to expand...
That perspective on the figures is genuinely helpful, and it holds together logically. For the past week I've been stepping on the scale every day and logging what I eat. My readings have hovered between 59.0 and 59.7kg across those days, so things look fairly steady — though my intake has been slightly lower than it was before I switched to this tirz batch.

This is the batch I got through a reseller, and honestly I'm not sure I trust the COA, or even that it originated from QYC. Only after plenty of back and forth between the reseller and the QYC rep did they finally confirm it. I suspect that has been nagging at me somewhat. Still, since suppression is quite pronounced, the vial must contain something — I'm simply not 100% certain it's entirely tirzepatide.

There's one more dose left in this vial. I'll give some thought to my next step, but I'm leaning toward pulling out one of my JEEP vials for the following round and seeing whether it changes how I feel. That batch has vendor and 3p testing behind it and has consistently come back good.

I'm truly grateful for all the guidance people have offered — it has helped me enormously.
 
GalloB73 said:

wiggle_zoom said:

Hi,

When I came down with the flu previously, I dropped 4-5 pounds over the course of a few days. I'm fairly confident the decongestant I was on acted as a diuretic in some way (the first night after taking it, I was up multiple times to urinate). Once the flu passed, those 4-5 pounds came back.

Given both the flu and whatever medication you've been taking, my guess is that this is simply water weight shifting around. The fact that you held steady for such a long period right before getting sick also suggests that the lower number was the outlier, rather than where you are now.

Let us know how it goes!
Click to expand...
That perspective on the figures is genuinely helpful, and it holds together logically. For the past week I've been stepping on the scale every day and logging what I eat. My readings have hovered between 59.0 and 59.7kg across those days, so things look fairly steady — though my intake has been slightly lower than it was before I switched to this tirz batch.

This is the batch I got through a reseller, and honestly I'm not sure I trust the COA, or even that it originated from QYC. Only after plenty of back and forth between the reseller and the QYC rep did they finally confirm it. I suspect that has been nagging at me somewhat. Still, since suppression is quite pronounced, the vial must contain something — I'm simply not 100% certain it's entirely tirzepatide.

There's one more dose left in this vial. I'll give some thought to my next step, but I'm leaning toward pulling out one of my JEEP vials for the following round and seeing whether it changes how I feel. That batch has vendor and 3p testing behind it and has consistently come back good.

I'm truly grateful for all the guidance people have offered — it has helped me enormously.
Click to expand...
Depending on what I did the day before and when I ate or exercised, my weight swings quite a bit as a matter of course. By the way, I've been sitting in my gw range for 3 months now.

The number on my scale this morning came in 2.2 lbs under yesterday's. So did I drop 2.2 lbs of fat overnight? No, that is not what happened.

I'm not trying to be snarky here (really), but 2.2 lbs is close to 1/2 of that 5.4 spike you saw. And that swing happened within a single day.

What actually occurred: the day before, my final meal landed 3 hours ahead of my usual time (3pm), and then at 6pm I spent 30 minutes on the elliptical, something I almost never do that late. I was simply bored and figured I'd work off some steam - and that is basically what took place. Water weight.

I'd bet good money that tomorrow morning's weigh-in comes in more than 1lb above this morning's.

You're doing great. Tirz is tirz no matter where it's acquired. Stay the course!
 
How did you end up at 3.8mg with the branded Mounjaro pens? That strength isn’t offered. Your dose must have been either 2.5mg or 5.0mg.
 
YoYoFat said:

How did you end up at 3.8mg with the branded Mounjaro pens? That strength isn’t offered. Your dose must have been either 2.5mg or 5.0mg.
Click to expand...
I stepped my dose down from 5mg by counting clicks. On a 5mg pen, 46 clicks equals 3.8 mg. For the remaining doses I drew them out with an insulin syringe; 0.46ml corresponds to 3.8mg.
 
Zydeceltico said:

GalloB73 said:

wiggle_zoom said:

Hi,

When I came down with the flu previously, I dropped 4-5 pounds over the course of a few days. I'm fairly confident the decongestant I was on acted as a diuretic in some way (the first night after taking it, I was up multiple times to urinate). Once the flu passed, those 4-5 pounds came back.

Given both the flu and whatever medication you've been taking, my guess is that this is simply water weight shifting around. The fact that you held steady for such a long period right before getting sick also suggests that the lower number was the outlier, rather than where you are now.

Let us know how it goes!
Click to expand...
That perspective on the figures is genuinely helpful, and it holds together logically. For the past week I've been stepping on the scale every day and logging what I eat. My readings have hovered between 59.0 and 59.7kg across those days, so things look fairly steady — though my intake has been slightly lower than it was before I switched to this tirz batch.

This is the batch I got through a reseller, and honestly I'm not sure I trust the COA, or even that it originated from QYC. Only after plenty of back and forth between the reseller and the QYC rep did they finally confirm it. I suspect that has been nagging at me somewhat. Still, since suppression is quite pronounced, the vial must contain something — I'm simply not 100% certain it's entirely tirzepatide.

There's one more dose left in this vial. I'll give some thought to my next step, but I'm leaning toward pulling out one of my JEEP vials for the following round and seeing whether it changes how I feel. That batch has vendor and 3p testing behind it and has consistently come back good.

I'm truly grateful for all the guidance people have offered — it has helped me enormously.
Click to expand...
Depending on what I did the day before and when I ate or exercised, my weight swings quite a bit as a matter of course. By the way, I've been sitting in my gw range for 3 months now.

The number on my scale this morning came in 2.2 lbs under yesterday's. So did I drop 2.2 lbs of fat overnight? No, that is not what happened.

I'm not trying to be snarky here (really), but 2.2 lbs is close to 1/2 of that 5.4 spike you saw. And that swing happened within a single day.

What actually occurred: the day before, my final meal landed 3 hours ahead of my usual time (3pm), and then at 6pm I spent 30 minutes on the elliptical, something I almost never do that late. I was simply bored and figured I'd work off some steam - and that is basically what took place. Water weight.

I'd bet good money that tomorrow morning's weigh-in comes in more than 1lb above this morning's.

You're doing great. Tirz is tirz no matter where it's acquired. Stay the course!
Click to expand...
I believe the main reason it rattled me so much is that my weight has barely moved at all since starting Mounjaro. I was losing a couple of pounds every week on a very consistent path, and once I reached my goal weight I went down to 3.8mg, where I was eating more and holding steady — staying in range with at most a 2lb difference week to week for roughly 6 months or longer. I already got through one Christmas and stayed the same then. The only difference this year was getting sick right beforehand and then making the switch to a grey tirz. It looks like things are settling down on their own now, so I'm feeling a bit calmer, and hearing everyone's experiences has genuinely helped. Back when I was obese I used to get these huge spikes constantly, driven by bingeing and restricting, so I think it just struck a nerve even though it's only a tiny blip along the way.
 
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