Weight loss
Tirzepatide, simplified.
Also called Mounjaro, Zepbound
Approved RxA weight-loss medicine that copies two fullness hormones at once, GLP-1 and GIP. People sometimes call it a "GLP-2", but that name really belongs to a different gut hormone.
- Size
- 39 amino acids
- How it is taken
- Weekly injection
- Status
- FDA-approved prescription
- Available sizes
- Vials: 5 mg, 10 mg, 15 mg, 20 mg, 30 mg, 60 mg
What is it?
Tirzepatide switches on two hormone signals your body already uses after meals: GLP-1 and GIP. Hitting both at once seems to curb appetite more strongly than GLP-1 alone.
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Official prescribing information
Zepbound and Mounjaro 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 72-week trial, adults with obesity on the highest dose lost about 21% of their body weight on average.
- In peopleIn a head-to-head trial against semaglutide, people lost about 20% of their weight on tirzepatide versus about 14% on semaglutide.
- In peopleIt is also approved to treat obstructive sleep apnea in adults with obesity.
What we don’t know yet
- How well weight stays off after stopping.
- Whether it protects the heart as strongly as semaglutide has shown. Those trials are still reporting.
Side effects and cautions
- Stomach side effects like nausea and diarrhea are common.
- Same thyroid cancer warning as semaglutide.
- Can make birth control pills less reliable for a while after starting or raising the dose.
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 Tirzepatide?
A weight-loss medicine that copies two fullness hormones at once, GLP-1 and GIP. People sometimes call it a "GLP-2", but that name really belongs to a different gut hormone. Tirzepatide switches on two hormone signals your body already uses after meals: GLP-1 and GIP. Hitting both at once seems to curb appetite more strongly than GLP-1 alone.
What does the research say about Tirzepatide?
In a 72-week trial, adults with obesity on the highest dose lost about 21% of their body weight on average. In a head-to-head trial against semaglutide, people lost about 20% of their weight on tirzepatide versus about 14% on semaglutide. It is also approved to treat obstructive sleep apnea in adults with obesity.
Is Tirzepatide FDA approved?
FDA-approved. Available only with a prescription.
What are the side effects of Tirzepatide?
Stomach side effects like nausea and diarrhea are common. Same thyroid cancer warning as semaglutide. Can make birth control pills less reliable for a while after starting or raising the dose.
Comes in these blends
- Tirzepatide + BPC-157 (30/1.3 mg, 60/2.6 mg vials): Tirzepatide + 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.