Cagrilintide
Cagrilintide
The other lever for fat loss — not a GLP-1 at all, but a long-acting amylin analog that works a different appetite pathway. On its own it’s a solid once-weekly weight-loss shot; the reason the community actually talks about it is that it’s the second half of the cagrilintide + semaglutide combination, where two different satiety signals stack instead of overlap.
What it is
People run it for fat loss, the same goal as the GLP-1 drugs — but it gets there through amylin rather than GLP-1, so the felt experience is described as a steadier, more “full and satisfied” fullness than the sharp food-noise shutoff of semaglutide or tirzepatide. Solo it’s a moderate-strength weight-loss shot. Its real draw is as the partner peptide: pair it with a GLP-1 and the two appetite systems add together.
The whole pitch is that it’s a different switch. Amylin is a hormone your pancreas already co-releases with insulin after a meal — cagrilintide is a long-acting copy of it, engineered to last about a week per shot. Because it isn’t a GLP-1, it doesn’t compete for the same receptor; it layers on top. That’s the entire logic of the famous cagrilintide + semaglutide combination the community watches closely: amylin satiety plus GLP-1 satiety, two signals instead of one, with the combination trial data landing in the same 20%-plus weight-loss territory people associate with the strongest drugs in the class.
Mechanism
An amylin-receptor agonist — a distinct pathway from the GLP-1/GIP/glucagon axis the rest of the fat-loss peptides work. Amylin signals satiety to the hindbrain, slows gastric emptying so a meal sits longer, and suppresses glucagon (blunting the post-meal sugar release from the liver). The net effect is eating less and feeling full sooner, by a different route than GLP-1’s. Mechanistic work points to amylin receptors in the brain (the AMY1/AMY3 subtypes) as where the bodyweight effect is actually driven. Because amylin and GLP-1 hit separate receptors, their satiety effects are additive rather than redundant — which is the mechanistic basis for the combination.
Standard dose
| Standard dose | 0.3–2.4 mg / week, titrated up (proposed — pending dosing review)clinical |
|---|---|
| Titration | Start low and step up over weeks — the dose-finding trial ran 0.3 → 0.6 → 1.2 → 2.4 mg, with 2.4 mg the effective top of the monotherapy rangeclinical |
| Frequency / route | Once weekly, SubQ — long-acting, built for a single weekly pinclinical |
| In combination | Run alongside a once-weekly GLP-1 (the cagrilintide + semaglutide pairing matched 2.4 mg of each); titrate both, don’t jump to top doseclinical |
Reconstitution calculator
U-100 · 100u = 1 mL= 200 units
Set the vial size and water to match your product — amounts vary by supplier. This is unit-conversion math, not medical advice or a dosing recommendation.
Pushing higher— going beyond the standard doseclinical
Side effects & cautions
The same GI profile as the rest of the fat-loss class: nausea is the most common, with vomiting, constipation, and diarrhea behind it — all worst during titration and easing as the dose settles. Unlike retatrutide, there’s no signature glucagon-driven heart-rate bump here, since it doesn’t touch the glucagon receptor as an agonist. Injection-site reactions show up. The combination with a GLP-1 stacks both drugs’ GI effects, which is the main reason both are titrated slowly. The usual class-wide concern — muscle loss with rapid weight loss — applies, so protein and training dominate the sane protocols. It’s investigational, so the long-term safety picture is still filling in.
Stacking
This is the peptide whose whole story is a stack. The defining pairing is with a GLP-1 like semaglutide — and the reason it works is that amylin and GLP-1 are different satiety pathways hitting different receptors, so their effects add rather than overlap. GLP-1 drives one arm of appetite suppression and insulin/glucose handling; amylin drives a separate satiety-and-slowed-emptying arm and suppresses glucagon. Two signals, two receptors, one combined effect — which is why the combination beats either drug run alone. The supporting work is the same as any aggressive cut: high protein, resistance training, electrolytes.
Evidence & sources
Real human RCT data exists — a Phase 2 monotherapy dose-finding trial (~10.8% loss at 26 weeks) plus Phase 2 and Phase 3 trials of the cagrilintide + semaglutide combination (REDEFINE), with the combination reaching ~20% body-weight loss. The honest caveat: it’s earlier-stage and investigational, not FDA-approved, and most of the headline numbers belong to the combination rather than cagrilintide alone — so the solo picture is more modest than the pairing people quote.
- Lau DCW et al. (2021)Human RCTOnce-weekly cagrilintide for weight management in overweight and obesity (Phase 2 dose-finding)Lancet — ~10.8% body-weight loss at 26 wk (monotherapy)PMID 34798060 ↗
- Frias JP et al. (2023)Human RCTCo-administered cagrilintide 2.4 mg with semaglutide 2.4 mg in type 2 diabetes (Phase 2)Lancet — combination, active-controlled RCTPMID 37364590 ↗
- Garvey WT et al. (2025)Human RCTCoadministered cagrilintide and semaglutide in overweight or obesity (REDEFINE 1, Phase 3a)NEJM — ~20.4% body-weight loss vs 3.0% placeboPMID 40544433 ↗
- ClinicalTrials.gov (2022)Trial registryREDEFINE 1 — cagrilintide + semaglutide Phase 3 obesity trialClinicalTrials.gov — completed Phase 3NCT05567796 ↗
- Oliveira Carvas A et al. (2025)Animal / in-vitroCagrilintide lowers bodyweight through brain amylin receptors 1 and 3eBioMedicine — receptor mechanism (knockout mice)PMC12270663 ↗