Cagrilintide guide & protocols

Cagrilintide is the compound most people meet as the other half of CagriSema, and that framing undersells it a little. It works on appetite through amylin rather than GLP-1, which makes it the first thing in years to come at the same problem down a different road. Below is the weekly schedule people actually run, how it's paired with semaglutide, and what the trial record says it does when nothing else is in the picture.

Vial size isn't part of what follows, since the amount of bacteriostatic water you add sets your concentration either way. Our reconstitution calculator handles that math for whatever vial and target amount you're working with.

What it is

Cagrilintide is a long-acting synthetic version of amylin, a hormone your pancreas releases alongside insulin every time you eat. Natural amylin is gone in minutes, which is why it was never much use as a drug. Cagrilintide was engineered to last about a week instead, which is what makes a once-weekly injection possible.

Amylin works on the brainstem and hypothalamus to signal fullness, slow how quickly the stomach empties, and quiet the glucagon spike after a meal. That's a different set of receptors from the ones semaglutide acts on, and the reason the two get combined rather than compared as substitutes. It's a close cousin of pramlintide, the shorter-acting amylin analog approved as Symlin, with the modifications that stretch its duration out to a weekly rhythm.

What people use it for

Weight and appetite is the whole conversation here, but the reason people go looking for cagrilintide specifically rather than another GLP-1 is usually one of two things. Some have run semaglutide or tirzepatide, hit a plateau, and want something that pushes on a different lever instead of a higher amount of the same one. Others didn't tolerate a GLP-1 well and are looking at whether a non-GLP-1 route to the same effect exists.

There's a smaller thread of interest in what amylin does to the quality of fullness rather than the quantity of food, since people describe it as feeling satisfied rather than blocked. That's self-reported and not something the trials measured, but it comes up often enough to be worth naming.

Formulations

Cagrilintide ships as a lyophilized powder that needs reconstitution before use. Across the vendors we track, 10 mg vials are the most common by a wide margin, with 5 mg the usual alternative and the occasional 8 mg listing. That's a meaningful change from a year ago, when this compound was genuinely scarce in research supply and the small vials that existed were priced accordingly. It's subcutaneous only; there's no oral version of this one at any tier.

One thing to note before buying: CagriSema is two separate compounds, not a premixed product. If the pairing is what you're after, that's two vials, two reconstitutions, and two lines on the price comparison, not one.

Dosing protocols

Cagrilintide sits in a small group of compounds on this site where the weekly amounts trace to published human research rather than to circulating convention. The two large studies that took it to the edge of approval, run under the name REDEFINE, which is the manufacturer's label for its research programme on the cagrilintide and semaglutide combination rather than a set of initials, both used a documented step-up schedule to a 2.4 mg weekly maintenance amount, and the pattern that circulates mirrors it directly. REDEFINE 1 was the study in people without diabetes and REDEFINE 2 the one in people with type 2 diabetes, and both names come up constantly on vendor pages, so they're worth recognising.

See the Cagrilintide research notes for the trial data and mechanism behind the numbers below.

Trial escalation schedule

The schedule used in the REDEFINE trials, stepping up every four weeks. This is what the circulating pattern is copying.

All amounts above are once-weekly subcutaneous injection.

Where the higher amounts come from

The 2.4 mg maintenance figure is not the ceiling that's been studied. An earlier study set out to find the right amount and ran seven once-weekly options, from 0.3 mg all the way up to 4.5 mg. The 4.5 mg group lost the most weight, so that amount does have real published research behind it rather than forum enthusiasm. It's referenced less often than 2.4 mg in practice, largely because the later work settled on 2.4 mg as the amount worth carrying forward alongside semaglutide.

Amount total, for planning your vial purchase: the 16-week escalation adds up to 13.8 mg (1 mg across weeks 1 to 4, plus 2 mg across weeks 5 to 8, plus 4 mg across weeks 9 to 12, plus 6.8 mg across weeks 13 to 16). Holding 2.4 mg weekly for the remaining 36 weeks of a first year adds 86.4 mg, for a first-year total of roughly 100 mg. Each year after that, held at maintenance, runs about 125 mg (2.4 mg times 52 weeks). If you're running the semaglutide pairing, double those totals, because the schedules are identical and you're buying both. Compare vendors on price per milligram against that total rather than against the price of a single vial.

How much to reconstitute at once: a reconstituted vial is generally good for about 28 days refrigerated, so what to mix at one time is whatever four weeks of the current step actually draws, not the whole vial. Four weeks at the 0.25 mg starting amount only uses 1 mg, so reconstituting a full 10 mg vial in week one leaves most of it expiring unused. At the 2.4 mg maintenance amount, four weeks draws 9.6 mg, which lines up almost exactly with a 10 mg vial. See how much to reconstitute at once for the general math.

Cycling guidelines

There's no on-then-off cycling convention for cagrilintide. What's described is a single escalation to a maintenance amount, held for as long as someone is actively pursuing the effect, and the trial structure reflects that: REDEFINE 1 ran 68 weeks, with the maintenance amount held for 52 of them. Where the compound is discussed in stretches, it's in months and years rather than weeks.

Whether weight comes back after stopping hasn't been tested for cagrilintide the way it has for semaglutide, where the STEP program measured regain directly. The reasonable expectation, given both compounds work by continuously signalling fullness rather than changing anything structural, is that the effect is tied to continued dosing. Nobody has published the number.

Signs a course is commonly stopped or reconsidered:

• Nausea or vomiting severe enough to interfere with eating or staying hydrated, most often right after a step up
• Severe or persistent abdominal pain, particularly if it radiates to the back
• Signs of a gallbladder problem, such as pain in the upper right abdomen or yellowing of the skin or eyes
• Injection site reactions that don't settle between weekly doses

Stacking

Most commonly paired stack: Cagrilintide with semaglutide, the pairing the trials call CagriSema.

Rationale: the two act on different receptor populations in the brainstem and hypothalamus, so the argument is that they're complementary rather than redundant. This is the rare stack on this site where the combination itself was actually studied, rather than a plausible mechanism and a hopeful schedule.

Protocol as run: both compounds escalated on the same four-week schedule to 2.4 mg each, injected weekly. In the trials they were coadministered, and what circulates mirrors that, two separate reconstitutions dosed on the same day rather than mixed in one vial.

What the combination actually added: in REDEFINE 1, mean weight reduction at 68 weeks was 20.4% for the combination, against 14.9% for semaglutide alone and 11.5% for cagrilintide alone. Among participants who stayed on treatment throughout, the combination figure was 22.7%. The gap between the combination and either compound by itself is the entire case for the stack, and it's a real measured gap rather than an inferred one.

Lighter stacks: the growth hormone pair, CJC-1295 with Ipamorelin, shows up here for the same reason it shows up alongside semaglutide, aimed at preserving lean mass through a sustained deficit. BPC-157 appears as gut support against the digestive side effects. Both are rationale plus a loosely matched schedule, with no combination data specific to cagrilintide.

Combinations to approach carefully: stacking cagrilintide onto tirzepatide or retatrutide instead of semaglutide is a reasonable-sounding extension of CagriSema that has no trial behind it. The published combination is with semaglutide specifically, and side effect profiles in this class are additive enough that swapping in a different, stronger GLP-1 partner isn't a small substitution.

Expected results timeline

Early weeks: the escalation period is mostly adjustment. Nausea is the most noticeable thing, and it tends to spike in the days after each step up and then settle. Appetite changes are usually apparent well before the scale moves.

Months in: once maintenance is reached, this is where the measured effects show up. The trial numbers everyone quotes were taken at 68 weeks, so the timeline the data actually supports is closer to a year and a half than a season.

Extended, continued use: REDEFINE 1 held the maintenance amount for 52 weeks after escalation, and the cumulative change built across that whole stretch rather than arriving early and plateauing.

What to expect realistically: the 11.5% monotherapy figure from REDEFINE 1 is a mean across a large trial population, and a mean hides a wide spread. It's also noticeably below the 20.4% the same trial measured for the combination, which is worth sitting with if you were planning to run cagrilintide by itself, since most of the impressive numbers attached to this compound's name belong to the pairing rather than to the compound alone.

Administration technique

1. The lyophilized powder is reconstituted with bacteriostatic water, at a concentration set by the reconstitution calculator for the target weekly amount.
2. The solution is swirled gently to dissolve rather than shaken, since agitation can degrade the peptide.
3. The calculated volume is drawn into an insulin syringe or similar fine-gauge syringe.
4. A subcutaneous site is chosen, commonly the abdomen or the front of the thigh, with sites rotated week to week.
5. The skin is pinched and the injection given at roughly a 45-degree angle, held for a few seconds before withdrawal.
6. Where semaglutide is being run alongside, the two are drawn and given as separate injections rather than combined in one syringe, which is how they were administered in the trials.
7. Each weekly injection is commonly logged by date, amount, and site, which matters here because the escalation runs four months before maintenance is even reached.

Side effects and safety

Common: nausea leads by a wide margin, and it tracks upward with the weekly amount, most noticeable right after a step up. Vomiting, constipation, and diarrhea follow the same pattern. Injection site reactions are reported more often for cagrilintide than for semaglutide.

Less common: gallbladder problems including gallstones are reported across this whole category, which is understood as a consequence of rapid weight loss itself rather than of any one mechanism. Pancreatitis is the rare concern flagged across the class.

What we don't know: cagrilintide has no approved pharmaceutical form anywhere, and as of mid-2026 regulatory review of the combination is ongoing. That means there is no prescribing information, no boxed warning, and no post-market surveillance record to read, which is a real difference from semaglutide and tirzepatide, where a decade of pharmacy-channel data exists behind the trial numbers. Long-run outcomes in people using research-grade material outside clinical supervision aren't tracked anywhere.

Contraindications: pregnancy, breastfeeding, and use in minors have no research-grade safety data behind them. A personal history of pancreatitis is the caution most consistently carried over from the GLP-1 class. Because amylin analogs affect glucagon and gastric emptying, anyone managing blood sugar with insulin or a sulfonylurea is in a genuinely different risk position than the trial populations, and that combination is where the clinical literature is most explicit about hypoglycemia risk.

Drug interactions: slowed gastric emptying changes how quickly anything taken by mouth around the same time is absorbed, including medications with a narrow effective range. That's the same interaction flagged in the prescribing information for approved GLP-1 products and is reasonable to expect here.

Cagrilintide vs. Semaglutide

Semaglutide is the compound cagrilintide actually gets cross-shopped against, partly because it's the standard everything in this category is measured by, and partly because REDEFINE 1 ran both of them as separate arms in the same trial, which is a cleaner head-to-head than this site usually gets to point at.

Choose cagrilintide if: you want the pathway that isn't GLP-1, either because a GLP-1 didn't suit you or because you're adding to one rather than replacing it.

Choose semaglutide if: the deeper trial history, the cardiovascular outcome data, and the existence of an actual approved product to compare against matter more than novelty of mechanism.

Stacking the two: this is the combination the whole research program was built around, and the 20.4% figure belongs to the pair rather than to either one. If the numbers that drew you to cagrilintide were CagriSema numbers, the stack is what produced them.

See the Semaglutide research notes for its own trial data, mechanism, and pricing.

Storage and handling

Lyophilized powder: refrigerate at 2 to 8°C for near-term use. Kept frozen, the unreconstituted powder is commonly described as stable considerably longer. Protect from light, and take lot-specific stability from the vendor's certificate of analysis rather than a general rule.

Reconstituted solution: refrigerate and plan to use it within about 28 days once water has been added. That figure comes from the compounding-pharmacy standard for a bacteriostatic-water solution, not from any manufacturer's in-use window, since cagrilintide has no approved product to borrow one from. Avoid repeated freeze-thaw cycles.

Signs of degradation:

• Cloudiness or visible particles in a solution that was previously clear
• Discoloration of the powder or the reconstituted liquid
• An appetite effect that unexpectedly stops showing up at an unchanged weekly amount, though that's a soft signal at best

FAQ

Is cagrilintide a GLP-1? No, and that's the point of it. It works on amylin receptors, which is a separate pathway, which is why the two get combined rather than chosen between.

Can I run it on its own? People do, and REDEFINE 1 measured it as a single agent at 11.5% mean weight reduction over 68 weeks. That's below what the same trial measured for semaglutide alone.

What is CagriSema? Cagrilintide and semaglutide at 2.4 mg each, weekly, escalated on the same schedule. It's two vials and two injections, not a premixed product.

How is it typically escalated? Starting at 0.25 mg weekly and stepping up every four weeks through 0.5, 1, and 1.7 mg to a 2.4 mg maintenance amount at week 17, which is the REDEFINE schedule.

Why do people mention 4.5 mg? An earlier study ran amounts up to 4.5 mg weekly, and that group lost the most weight. The later research carried 2.4 mg forward instead, so 4.5 mg has real support behind it but far less circulating use.

How long do people run it? The trial structure held maintenance for 52 weeks after a 16-week escalation, and the compound is discussed as an ongoing commitment rather than a short course.

Is it approved anywhere? No. Regulatory review of the combination was still ongoing as of mid-2026, so there's no prescribing information behind any of this.

How is it stored? Refrigerated as a powder, refrigerated and used within about 28 days once reconstituted.

Bottom line

Key dosing takeaways:

• Escalating from 0.25 mg weekly to a 2.4 mg maintenance amount over 16 weeks is the pattern that circulates, and it traces directly to the REDEFINE trial schedule rather than to forum consensus
• Most of the headline numbers attached to cagrilintide belong to the semaglutide pairing; as a single agent the same trial measured 11.5%
• 4.5 mg weekly has real published support behind it but is much less commonly referenced, since the later research carried 2.4 mg forward

Best practices:

• Price this against a realistic first-year total of roughly 100 mg, and double it if you're running the semaglutide pairing, rather than comparing single vial prices
• Reconstituting only what the current step draws in four weeks avoids throwing away most of a 10 mg vial during early escalation
• Logging each weekly injection matters more than usual here, since escalation runs four months before maintenance starts

Works best for people who:

• Want a non-GLP-1 route to appetite regulation, whether as an addition or an alternative
• Are comfortable with a compound that has good trial data and no approved product, prescribing information, or post-market record behind it
• Are prepared for a months-to-years commitment rather than a short course

Cagrilintide is sold for research, and there are no large human trials establishing a safe long-term profile in people using research-grade material outside a trial. You already know that. You're an adult making an informed call about your own body, and that's yours to make.