Advice sought - weight spike on transition from Mounjaro to QYC tirzepatide

GalloB73

GLP-1 Apprentice
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Hi all,

I don't think this is anything to worry about but seeing as I haven't gained anything over about 1lb for the past year I thought I'd ask in case anyone had any insight if a similar thing happened to them.

I've just started using grey market tirzepatide (from QYC). I've been in maintenance mode for over a year, target weight range is between 59-61kg (130-134lbs).
Dose has been 3.8mg a week (prescribed Mounjaro pens previously) for over a year.

My first batch I got from a reseller as I didn't really know what I was doing. I was told these were QYC products and confirmed with QYC that was true. They sent me their vendor Janoshik COA which showed average fill for this batch to be 30.46mg over two vials (31.81/29.11). I reconstituted with 3.2ml of vendor BAC and filtered into a sterile vial all using aseptic technique. Have administered 0.4ml twice now (3.75mg), but my weight has spiked by 2.45kg (5.4lbs), from my lowest weight the week before Christmas (so 4 weeks).

I did get very strong suppression and some slight stomach pain with my first dose so I thought maybe there was a chance it was overfilled so I split the second dose to see if it would ease which it did. I just didn't expect the scale to rise for the second week in succession.

Table below shows it a bit clearer:


Date5 Nov12 Nov19 Nov26 Nov03 Dec10 Dec17 Dec24 Dec31 Dec7 Jan14 Jan
Weight59.258.358.4/57.95/57.10//59.0059.55
dose3.8mg MJ3.8mg MJ
3.8 MJ​
3.8mg MJ3.8mg MJ3.8mg MJ3.8mg MJ
3.8mg 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 have a feeling I'm overthinking it as it's my first time using grey and I'm so scared about putting weight on after being obese most of my life. I know 100% I will be a life long GLP1er. I've since made another order for JEEP tirzepatide which I have in storage and my batch has got quite a lot of vendor and 3p testing. I've also got a few bottles of Hospira BAC coming in about 10 days.

I'm paying very close attention to what I eat now, but apart from Christmas week when I did eat more than normal nothing really has changed. Still lifting 3x a week but this is the first time I've had such a rapid gain in such a short period of time. Is this normal when transitioning to grey? I keep telling myself there is no way I could have eaten the required calories for it to be fat. Even on Christmas day I only managed to eat one meal, albeit a comparatively big one to what I'm used to.

I have been below my lower weight target for a few weeks anyway and am 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.
 
Last edited:
If you got strong suppression from your first dose of the QYC tirz, I doubt the product is bunk. Looks like you’re taking the necessary steps to monitor your food intake. Personally, I wouldn’t overthink it. Perhaps you log your food and water intake for a couple of weeks and see where you land.
 
Based on your being ill and other comments, I'd give it a couple more weeks tracking what I eat and see what happens. I have weight daily for over a year tracking my progress and it amazes me how much my weight varies up and down each day. As long as I'm eating right, tracking my intake, and exercising, the overall trend has been the correct direction. Lots of things affect weight in the short term. Good luck and hang in there.
 
If you got strong suppression from your first dose of the QYC tirz, I doubt the product is bunk. Looks like you’re taking the necessary steps to monitor your food intake. Personally, I wouldn’t overthink it. Perhaps you log your food and water intake for a couple of weeks and see where you land.
Thank you this is really helpful.
 
I've only ever been on grey. It works. And if it doesn't, maybe it's an under fill. Or... maybe Christmas is partially to blame🙂 but I agree with @testyonenow42, weight fluctuations happen. As long as they get us there overall🙂
 
I've only ever been on grey. It works. And if it doesn't, maybe it's an under fill. Or... maybe Christmas is partially to blame🙂 but I agree with @testyonenow42, weight fluctuations happen. As long as they get us there overall🙂
Yes I need to see the big picture not just the last few weeks. Thank you.
 
Based on your being ill and other comments, I'd give it a couple more weeks tracking what I eat and see what happens. I have weight daily for over a year tracking my progress and it amazes me how much my weight varies up and down each day. As long as I'm eating right, tracking my intake, and exercising, the overall trend has been the correct direction. Lots of things affect weight in the short term. Good luck and hang in there.
Thank you that’s useful to read. After pretty much flatlining my weight for over 6 months I think I just panicked this morning, probably a bit of a hangover form all the previous loss/gain cycles I’ve been through.
 
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