Weight loss · Aging & longevity
Semaglutide, simplified.
Also called Ozempic, Wegovy, Rybelsus
Approved RxA lab-made copy of a gut hormone called GLP-1 that tells your brain you are full. It is the active ingredient in Ozempic and Wegovy.
- Size
- 31 amino acids
- How it is taken
- Weekly injection or daily tablet
- Status
- FDA-approved prescription
- Available sizes
- Vials: 5 mg, 10 mg, 15 mg, 20 mg, 30 mg
What is it?
After you eat, your gut releases a hormone called GLP-1. It tells your brain you have had enough and slows how fast your stomach empties. Semaglutide acts like GLP-1 but lasts about a week instead of a few minutes.
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Official prescribing information
Wegovy and Ozempic are FDA-approved. The official label shows how it was dosed in the trials that led to approval, along with warnings and who should not use it.
Doses on the label are for the approved product under a prescriber’s care. Talk with your doctor before starting anything.
What studies show
- In peopleIn a large 68-week trial, adults with obesity lost about 15% of their body weight on average, compared with about 2% on placebo.
- In peopleIn a trial of 17,000+ people with heart disease and excess weight, it lowered the risk of heart attack, stroke and heart-related death by about 20%.
- In peopleIt lowers blood sugar in type 2 diabetes, which is what it was first approved for.
What we don’t know yet
- Most people regain much of the weight after stopping.
- Very long-term effects past a decade are still being studied.
Side effects and cautions
- Nausea, vomiting, diarrhea and constipation are common, especially early on.
- Rare risks include pancreatitis and gallbladder problems.
- Not for people with a personal or family history of medullary thyroid cancer or MEN2.
Is it legal?
FDA-approved. Available only with a prescription.
Dosage & schedule evidence
How to read published schedules
FDA-approved products exist for specific indications, and schedules vary by product, indication, and formulation. Follow the current official prescribing information and your clinician's instructions.
| Measurement | Meaning |
|---|---|
| 1 mg | 1,000 mcg (mass) |
| 100 U-100 units | 1 mL (volume, not dose) |
For source context, see third-party published protocols ↗. North Star does not validate these schedules.
Consult your doctor before considering any peptide for personal use. Educational only, not administration guidance.
Common questions
What is Semaglutide?
A lab-made copy of a gut hormone called GLP-1 that tells your brain you are full. It is the active ingredient in Ozempic and Wegovy. After you eat, your gut releases a hormone called GLP-1. It tells your brain you have had enough and slows how fast your stomach empties. Semaglutide acts like GLP-1 but lasts about a week instead of a few minutes.
What does the research say about Semaglutide?
In a large 68-week trial, adults with obesity lost about 15% of their body weight on average, compared with about 2% on placebo. In a trial of 17,000+ people with heart disease and excess weight, it lowered the risk of heart attack, stroke and heart-related death by about 20%. It lowers blood sugar in type 2 diabetes, which is what it was first approved for.
Is Semaglutide FDA approved?
FDA-approved. Available only with a prescription.
What are the side effects of Semaglutide?
Nausea, vomiting, diarrhea and constipation are common, especially early on. Rare risks include pancreatitis and gallbladder problems. Not for people with a personal or family history of medullary thyroid cancer or MEN2.
Comes in these blends
- CagriSema (5/5 mg, 10/10 mg vials): Cagrilintide + Semaglutide
- Semaglutide + BPC-157 (5 mg/650 mcg, 30/3.5 mg vials): Semaglutide + BPC-157
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This page explains published research in plain language. It is not medical advice, a diagnosis, or a recommendation to take anything, and it does not give dosing. Most peptides here are not FDA-approved, and products sold online vary widely in purity. Rules around peptides are changing, so check the current status and talk with a licensed clinician before starting anything. Last reviewed 2026-10-19.