World

This one is worth a read. A new 2026 Nature Metabolism study looked specifically at cagrilintide + retatrutide and found some interesting synergy beyond what you might expect from simply stacking appetite suppression.

Study setup:
Obese male rats were given Cagri, Reta, or the combination. The researchers also compared Cagri + Reta against Cagri + semaglutide and Cagri + tirzepatide.

Core protocol:
• Cagri: 5 nmol/kg/day
• Reta: 5 nmol/kg/day
• Subcutaneous administration
• Approximately 2 weeks depending on the experiment
• Additional dose-response testing from 0.3–30 nmol/kg

Results:
Cagri + Reta produced greater reductions in body weight and food intake than either compound alone at matched molar doses.

But the pair-fed experiment is what really caught my attention.

Researchers included animals restricted to the same food intake as the Cagri + Reta group, along with calorie-restricted animals used to separate the effects of reduced intake and weight loss from the pharmacology itself.

The combination still produced metabolic and molecular changes that weren't completely explained by eating less.

That's interesting because Cagri often gets viewed simply as an additional appetite suppressant alongside Reta.

Mechanistically, you're combining:

Reta → GLP-1 + GIP + glucagon receptor activity
Cagri → amylin-receptor activity

Together, researchers observed changes involving central energy-balance pathways and peripheral bioenergetic/metabolic pathways, along with improvements in markers including insulin, triglycerides and total cholesterol.

The study also found the Cagri + Reta combination produced stronger weight-loss effects than the Cagri + semaglutide and Cagri + tirzepatide combinations tested.

Big takeaway for me:
Cagri + Reta may be considerably more interesting than simply “Reta with extra appetite suppression.” The pair-fed data suggest complementary metabolic effects that extend beyond calorie reduction alone.

Study: Cagrilintide and retatrutide combination therapy enhances weight loss and metabolic outcomes in obese male rats — Nature Metabolism, 2026.

That pair-fed experiment is the part I'd really like to hear everyone's thoughts on. As well as the possibility of using it alongside reta to achieve results quicker and with more price efficiency.

had ChatGPT summarize this.

Why I had chat summarize: #1 being time of course... as well as having just purchased Cag to stack in with reta. In my endeavours I experienced a run in with a fellow researcher claiming adding cag and lowering reta was a profoundly stupid idea. 2 days later this study is dropped and proves that it may indeed be worth researching as it has not only showed greater results when combined it also will help to limit my expenditures on Reta.

This is a vendor review submitted by ricksporrer on PeptideCritic.com.

Rating: (3/5) · Peptide: 5-Amino-1MQ · Reviewed September 27, 2026

The product was not Amino -1MQ. The product was an amino blend. The report shows that most of the content is not present in the amino mix. I bought an amino mix with 10 amino acids and only two of…

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I've now been on compounded Tirzepatide through a Telehealth company for about 10 months now, and it has completely changed my life. My SW: 332 lbs, CW: 244.6 lbs and my goal weight is between 200-215 lbs. I'm so grateful for these meds and what it's done for me especially how I viewed food.

Hi peeps,

I recently got some 10mg slu-pp-915 capsules from disguised alpha. Subjectively the research animals seems to have a significant boost in energy for workouts and some notable last stage fat loss (ie last lower abdominals and posterior waste/hip) which is typically difficult and slow.... The odd thing I wanted to get some input on is that these are powder filled capsules. They looked pink ish which isn't odd for disguised alpha. Out of curiosity I opened one up and noticed the actual powder inside is a distinct orange/red color which was showing through the otherwise fairly white capsule. Does anyone else have any experience with this compound? Does this color seem normal? I was expecting a white/off white based on what info I could find on the webz. I reached out to DA to ask if this was the typical color or the powder. Just kinda was a shocking color from most other whitish powder that compounds normally are (-ghkcu). Thanks for any input

Have a 120lb female that would like some advice on dossing? She is currently researching KLOW 2.5mg daily and Reta 0.5 each week. Considering 1mg each day of SS-31. What time of day?

This is a vendor review submitted by BBLDarkstar on PeptideCritic.com.

Rating: (5/5) · Peptide: Cagrilintide · Reviewed September 27, 2026

My most recent order with crush was only a single vial of Cagrilintide. Ordered Wednesday night, showed up Friday. Packaging is best I've seen. Over never had a single issue with any of my Crush…

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New to peps, has anyone used Glaciers Mito Blend and if so what is proper dosing for beginning and maintenance - thx.

In this video, Jeff and Randy demonstrate the V4 Plastique, the next step in reusable peptide pen design. It delivers up to 60 units, leaves substantially less solution behind than the V1 and many other pen models, and will not dial past the amount remaining in the cartridge. If only 12 units are left, the pen stops at 12, so you know what can actually be delivered.

That low-residual design comes with a tradeoff: the V4 Plastique requires a firmer push than the standard V4. I compare the two designs, explain why the mechanism feels different, and cover who may prefer reduced waste over the lightest possible injection stroke.

https://x.com/PeptideCritic/status/2102125721909108854?s=20

https://rumble.com/v7fsrxc-v4-plastique-pen-explained-60-unit-delivery-less-waste-and-smarter-dosing.html

Apologies if this is the incorrect place for this post. I figure it has to do with pens, so this may work?

I've recently made the switch to peptide pens and have become a huge fan of the convenience and consistency (thanks Randy!). Since I'm also on TRT, I started wondering whether testosterone could be used with pens as well.

After finding a forum thread where several people were doing exactly that, I decided to run some tests of my own.

Goal: Determine whether Testosterone Cypionate can be delivered accurately and consistently through a peptide pen.

Setup:
Pen: ConviPen (auto-injector)
Testosterone: Testosterone Cypionate 200 mg/mL in cottonseed oil
Needles: EasyTouch 29g 1/2" pen needles

I chose the ConviPen because it uses a metal drive rod and I suspected an auto-injector would have an easier time pushing a more viscous oil. I am still considering testing a manual pen (V4) for comparison.

Testing Performed:
Test #1: I loaded a cart into the pen and measured output directly into an insulin syringe. To do this, I inserted the syringe into the cart and dispensed a dose from the pen, allowing me to measure the volume.

Approximately 10 repetitions were performed.

Result:
Output was extremely consistent.
15 units delivered essentially what was expected each time.

Test #2: I then attached a 29g pen needle and repeated the testing by dispensing through the needle into the open end of a syringe. This method was less precise than Test #1, as some of the oil adhered to the sides of the syringe and could not be measured perfectly.

Approximately 30+ repetitions were performed.

Result:

Output remained consistent.
Measured delivery was roughly 1 unit lower than expected.
Because of this, I began testing a setting of 16 units to achieve an effective 15-unit delivery.

Test #3: I then did an actual subcu injection for my regular dose. When I pressed the trigger at 16 units, the dose indicator rapidly dropped to approximately 5 units remaining, then continued clicking all the way down to 0. I left the needle in place for approximately 10 seconds after the indicator reached 0.

This behavior was very different from my syringe testing and raises the question of whether tissue resistance affects delivery compared to bench testing.

Preliminary Conclusions:
• Testosterone Cypionate in cottonseed oil can be delivered through a peptide pen.
• A 29g pen needle appears to work (shout out to the forum users who stated this in another post!!)
• Pens are mechanically capable of pushing oil-based testosterone.
• I still need long-term validation through TRT labs to confirm that Total Testosterone and Free Testosterone remain consistent with pre-pen values.
• I am unsure whether an auto-injector or manual pen is ultimately the better platform for oil-based compounds.

Questions: For those who have experimented with TRT in peptide pens:
• Have you found auto-injectors or manual pens to be more reliable?
• Has anyone validated dose accuracy through bloodwork or measured output testing?
• What are some other factors I should be considering?

I'm still early in this experiment, but so far, things are looking promising!

P.S. For those wondering, I wasn't burning through my actual TRT supply for science. A friend had an old blended testosterone vial that was never going to be used, so it became the sacrificial test subject for this project.

This was me at my heaviest at 332 lbs. And today coming in at 243 lbs. thanks to compounded Tirzepatide and hitting the gym. And yes, that is a fitting room selfie from Cabela's.

Watch on RandyTube: Disposable Peptide Pens | Types & How to Load Them (Step-by-Step Tutorial)

This comprehensive tutorial provides an overview of disposable peptide pens, covering the different types available and their specific features. Learn step-by-step instructions for properly loading these pens, including essential tips for maintaining sterility, handling cartri…

Comments posted here show up under the video on PeptideCritic.com, and vice versa. Questions about the technique, gear or the math are all welcome.

Is Anhedonia really a side effect? Anhedonia by its literal Greek definition means "without pleasure". The exact opposite of anhedonia is hedonia, which is the normal human capacity to experience pleasure, comfort, and satisfaction. Thats is where Hedonism comes from. Hedonism is the philosophical and lifestyle belief that pleasure and happiness are the highest goods and the ultimate aims of human life.

So what gives? Glp-1 bunts the hedo' in you. We can titrate up and we can titrate down. Were we given a control dial? Do we really have it this good?

Got a chance to get in on a GB for this but can't find any protocol on it. Reta 10mg / Elora 2.5 mg

On Southern Aminos website, I viewed Adamax (that's what I was looking for).
When I clicked on the selection, I had two options Adamax Prime ($42) and Adamax Apex ($70.40). When I looked at the COAs, they both showed only Adamax and at a 99.3-99.5% purity (roughly). My point is that both vials, per the MOA, have 10mgs of high purity Adamax. Why is one significantly more expensive. Like I said, the COAs only show Adamax; neither are blends and Both Show 10mgs.
I asked via email,

"Please explain the difference between Adamax Prime and Adamax Apex? They appear to both be the same amount in mgs, and both high grade Adamax, so why is Apex much more expensive? I thought perhaps Apex was a blend, but no other peptides are shown on the COAs.
I want to buy Adamax but need to know the answer to my question before making a purchase."

I have not received a response to my email, which was sent three days ago. If someone knows, please let me know. I purchased Adamax from another vendor this time, but with 60% off, I wanted to take advantage and get a lot.
Thank you!
Joel

My hunch and semesters of Organic Chemistry paid off. I took the GIP out of the equation and the constipation is gone! No powdered muck, softeners, etc. (I figured most of you knew about this GIP problem already.) If you had normal movement before, you'll have it again. It takes about 2 weeks or so for the GIP to leave your system and the gut to relax into normal peristalsis and it's so worth it!

I've lost the vast majority of weight I needed to lose; the rest will be slower anyway and it's more than a fair trade-off for 30 minutes on the porcelain and an asshole that's sore, cracked and bleeding at times. The constipation caused more fatigue than I thought, therefore, more natural energy is returning. Anxiety also accompanied all this, whether conscious of it or not. Just a general feeling of relief followed this battle.

I realize there are many of you who don't mind taking the usual meds for this issue but please consider that there's a high likelihood you will be harmed by continued constipation; whether with polyps or worse. I'm speaking from experience.

For those of you who've reached a point where you don't want to fight it anymore, a combo of Cagri (on Fri night) & Survo (on Tues night) might help you and I take near starter doses of each. I can't swear for every individual on this forum, butt, it might be worth a try.

For the record, I do use other peps: NAD+buf & MOTS-C both in AM and KPV before bed.

Wishing Y'all great Holiday sales!

For those of you who do a lot of testing, I know the fees get very expensive. In the current inflationary market, most people have far less disposable income than before. This is also expensive, but if you plan to buy peptides for the coming years and continue sending batches out for testing, this may be way to mitigate the costs. Like I said, it's expensive. If you have a business, you can always deduct a significant portion from tax returns. Someone could also charge lesser prices than the big labs and start a testing business.
So, if any of these things apply to you, here is a link to buy a machine to do peptide testing:

https://amc-essentials.com/shop/uv-visible-spectrophotometer-for-dna-rna-protein-analysis-1-8-nm-bandwidth/

Probably not for many, but it could be for some of you.

This is a vendor review submitted by Jaypeg on PeptideCritic.com.

Rating: (5/5)

Review

Placed my second order from flawless this week first order was for some Tesa and Reta. Delivered in two days after hitting buy. So far no issues Coas were readily available online. But will update if any of the multiple vials I have give me issues but so far they seem pretty reasonably priced.

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Dear Peptide Critic Community,

The GenPeptide Team wishes to thank you for all the support you have given us over the past several months. We are excited to announce that we will be transitioning to 7x testing for all new peptide batches, and we anticipate having 90% of our products with 7x testing by the end of 2026. We have also added endotoxin and heavy metal testing (5x testing) to 10 current batches.

Batches currently with 7x testing (identity, purity, mass amount, endotoxins, sterility, heavy metals, conformity):

• Tirz-GP (GLP-2TZ) 60 mg - GPTIR60090526
• KLOW - GPKLO80090526
• Reta-GP (GLP-3RT) 10 mg - GP-3P1008192026-04
• SS-31 30 mg - GP-ATP3008152026-02

Batches with 5x testing (identity, purity, mass amount, endotoxins, heavy metals):

• BPC-157 10 mg - GPBPC10051626
• Cagrilintide 5 mg - GPCAG05061726
• GHK-Cu 50 mg - GPGHK50061726
• GHK-Cu 100 mg - GPGHK100053126
• KPV 10 mg - GPKPV10071226
• MOTS-C 10 mg - GPMOT10080426
• NAD+ (buffered) 500 mg - GPNAD500071326
• Tesamorelin/ipamorelin blend 10/3 mg - GPTEI103071326
• Tirz-GP (GLP-2TZ) 20 mg - GPTIR20061726
• Tirz-GP (GLP-2TZ) 30 mg - GPTIR30071326

We also wish to announce expanded build-a-kit functionality. We now include the option of a 10-vial kit (30% off), in addition to the 5-vial kit (20% off). These kits are mix-and-match and can include any product on our website in any combination you choose.

Thank you for your continued support.

GenPeptide Team

Below is supposedly UBT251 molecular structure from patent https://patents.google.com/patent/CN117062618B/en noted in today's k-hole article https://krysia0430.substack.com/p/has-the-grey-market-worked-out-what

I expected much more differences
UBT251: Y-Aib-Q-G-T-αMeF-T-S-D-Y-S-I-αMeL-L-D-K-K(AEEAc-AEEAc-γGlu-CO(CH₂)₁₈COOH)-A-Q-Aib-A-F-I-E-Y-L-L-E-S-H-P-S-S-G-A-P-P-Ac3c-S-NH₂

Reta: Y-Aib-Q-G-T-F-T-S-D-Y-S-I-αMeL-L-D-K-K(AEEA-γGlu-C20)-A-Q-Aib-A-F-I-E-Y-L-L-E-G-G-P-S-S-G-A-P-P-P-S-NH₂

It works better than reta. Here is some comparison found on internet

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