Semaglutide
The flagship GLP-1 receptor agonist, the same molecule behind Ozempic and Wegovy. People run it for appetite control and weight loss, dosed once a week and titrated up slowly to keep side effects manageable.
Where to buy Semaglutide, cheapest first.
Prices from 4 vendors across the market. We link straight to each vendor’s product page and grade vendors on public lab data, so you’re not just chasing the lowest number.
Semaglutide
What Semaglutide actually does.
The simple version first, then a little more for the curious. No biochem degree required.
It mimics a gut hormone that tells your brain you're full, so you eat less without fighting constant hunger, while it also slows how fast your stomach empties.
How it works
Semaglutide is a long-acting copy of GLP-1, a hormone your gut releases after eating. It binds GLP-1 receptors in the brain's appetite centers, turning up the neurons that signal fullness and turning down the ones that drive hunger, so you naturally eat less.
Where it acts
It works in the hypothalamus and brainstem to cut appetite, and in the gut to slow gastric emptying so food stays with you longer. It also nudges the pancreas to release insulin only when blood sugar is high, which is why it started life as a diabetes drug.
What people notice
Most people describe a quieter appetite and far less food noise within the first few weeks, then steady weight loss over months. Effects build with each dose increase, not overnight, and they lean heavily on eating less overall.
Honest caveat: unlike most research peptides, semaglutide has large, high-quality human trials behind it (the STEP program showed roughly 15% average body-weight loss over 68 weeks). The honest caveat is different here: vendors in this space sell it for research use only, not as the FDA-approved prescription product, so purity and dosing accuracy are on you. None of this is medical advice, talk to a licensed provider before starting anything.
How to take it.
Semaglutide is a once-weekly subcutaneous injection into the fat with a tiny insulin needle. The defining feature is slow titration: you start low and step the dose up every four weeks so your gut can adjust. The routine is below; for the full titration schedule, see the guide.
Reconstitute the vial
Add bacteriostatic water down the side of the vial (a 5mg vial + 2mL = 2.5mg/mL). Swirl gently until clear, don't shake.
Draw your dose
On a U-100 insulin syringe, pull to your unit mark. At the 0.25mg start dose and 2.5mg/mL, that is 10 units (0.1mL). Use the calculator to match your own vial.
Pinch and inject
Swab with alcohol, pinch a bit of fat, insert at 45–90°, push slowly. The abdomen is simplest; the thigh or back of the upper arm also work.
Same day each week
Pick one day and stick to it. Step the dose up only every four weeks, and rotate sites. Store the vial in the fridge between doses.
The easiest spots are the belly (about 2 inches either side of the navel), the love handles, the front of the thigh, and the back of the upper arms. Rotate every injection.
Don't do the math, let the calculator do it.
This is Semaglutide's typical setup, already worked out. Change any value and the draw updates instantly.
Typical Semaglutide dose: start at 0.25 mg once weekly for four weeks, then step up every four weeks through 0.5 mg, 1 mg, and 1.7 mg, to a maintenance dose of up to 2.4 mg once weekly. The slow titration is the whole point, it keeps nausea manageable.
Cycling Semaglutide.
Whether Semaglutide is cycled at all, how long people run it, and the honest reasoning behind it.
Titrated up slowly to a maintenance dose, not cycled.
Semaglutide is different from most peptides here: it is not really run in short cycles. The prescription pattern is to titrate up and then stay on a maintenance dose for as long as it is working, because the appetite effect fades and weight tends to return when you stop.
That said, plenty of people do plan an eventual taper rather than stopping cold, and some stop once they hit a goal and accept that they will need to manage appetite by other means. There is no clean cycle-on, cycle-off rule the way there is with a recovery peptide.
- Titrate slowly through the first 16 weeks, stepping up only every four weeks at most.
- Hold at your effective dose rather than always pushing to 2.4 mg. The lowest dose that quiets your appetite is the right one.
- Plan the off-ramp. Weight tends to return after stopping, so think about diet and habits before you taper. That is a conversation for a licensed provider.
Want the full picture, on and off periods, the washout, stacking, and keeping your results? Read how peptide cycling works →
What's actually in the vial.
For one of these vendors we link the per-batch certificate itself, and the purity below is read straight off it. The rest link to the vendor's general lab-results page. We don't run the labs ourselves and we don't show a purity number unless it's printed on a certificate we link, so you can open the document and check it against the batch yourself.
| Vendor | Purity (per COA) | Batch / report | Certificate |
|---|---|---|---|
| Midwest Peptide | 99.856% | MPSM001 | View COA ↗ |
| Onyx Biolabs | see lab page | not shown | Lab results ↗ |
| Penguin Peptides | see lab page | not shown | Lab results ↗ |
What people pair it with.
Semaglutide is often run on its own, but these are the combinations the community reaches for when the goal is faster or deeper weight loss.
Amplified weight loss
The headline GLP-1 pairing. Cagrilintide is a long-acting amylin analog that hits a second satiety pathway; layered on semaglutide it pushed average loss past 20% in trials. Two satiety levers instead of one.
View stack →Recomp leaning
Some people pair the appetite control of semaglutide with a GH-peptide combo in the hope of protecting lean mass while losing fat. The evidence for the combo is thin, treat it as experimental.
View stack →Gut comfort
Because semaglutide is hard on the gut, some run BPC-157 alongside it for nausea and digestive comfort. This is community practice, not a tested protocol.
View stack →In the same corner.
Other weight and metabolic peptides people compare against Semaglutide.
Questions, answered straight.
Is Semaglutide legal?
Semaglutide is an FDA-approved prescription medicine (Ozempic, Wegovy, Rybelsus), but the vials the vendors we compare sell are offered strictly for research use only, not as the approved product. It is also on WADA's prohibited list as of 2026, so competing athletes should steer clear. Rules vary by country, so check what applies where you are.
What does research use only actually mean?
It means the product is sold for laboratory and research purposes, not as a supplement or medicine for people. These vials are not the FDA-reviewed pharmacy product, so purity and dose accuracy are not guaranteed. We aggregate prices and public lab data so you can see the landscape; what you do with that is between you and a licensed provider.
How do I store it?
Keep the sealed, freeze-dried vial in the fridge and out of direct light. Once you mix it with bacteriostatic water, store it refrigerated and use it within a few weeks. Don't freeze a reconstituted vial.
Why start at such a low dose?
Because semaglutide's side effects, mostly nausea and gut upset, are dose-driven. Starting at 0.25 mg and stepping up every four weeks gives your stomach time to adjust. Skipping the titration is the main reason people feel terrible and quit.
How is it different from Tirzepatide?
Semaglutide hits one receptor (GLP-1). Tirzepatide hits two (GIP and GLP-1) and tends to drive more weight loss in head-to-head trials, though it can be harder on the gut. Both are once-weekly subcutaneous injections that titrate slowly.