Semaglutide vs tirzepatide
The two ingredients behind most GLP-1 prescriptions. Shown here through their weight-management brands, Wegovy and Zepbound.
Semaglutide acts on the GLP-1 receptor; tirzepatide acts on both GIP and GLP-1. Semaglutide also comes as a daily tablet; tirzepatide is an injection only.
| Wegovy | Zepbound | |
|---|---|---|
| Active ingredient | semaglutide | tirzepatide |
| Made by | Novo Nordisk | Eli Lilly |
| Form | Injection | Injection |
| Schedule | Once a week | Once a week |
| How it works | GLP-1 receptor agonist | GIP and GLP-1 receptor agonist |
| Brands | Ozempic, Wegovy, Rybelsus, Wegovy pill | Mounjaro, Zepbound |
| Tablet available | Yes (Rybelsus, Wegovy pill) | No |
| Half-life (label) | about 1 week | about 5 days |
Key differences
- Semaglutide’s half-life is about a week; tirzepatide’s about 5 days.
- Both are weekly injections that start low and step up about every 4 weeks.
- Both are also made by compounding pharmacies; compounded versions are not FDA-approved.
Questions
Can Steady track both?
Yes. Pick your medication in the quiz and Steady uses its schedule, dose list and half-life for your level curve.
What is the difference between Wegovy and Zepbound?
Semaglutide acts on the GLP-1 receptor; tirzepatide acts on both GIP and GLP-1. Semaglutide also comes as a daily tablet; tirzepatide is an injection only.
Which is stronger, Wegovy or Zepbound?
Doses are not comparable milligram for milligram between different products, and which works better depends on the person. That is for your prescriber to judge.
Can I take Wegovy and Zepbound together?
The labels say these medications should not be used together with other GLP-1 receptor agonists. Do not combine them unless your prescriber tells you to.
How long do Wegovy and Zepbound stay in your system?
The labels give a half-life of about 1 week for Wegovy and about 5 days for Zepbound. It usually takes about five half-lives for most of a dose to clear.
Do Wegovy and Zepbound have the same side effects?
Both labels list stomach and gut effects such as nausea, diarrhea, vomiting and constipation as the most common. The full lists differ; see each medication’s side effects page.
Can I switch from Wegovy to Zepbound?
Only your prescriber can decide that and set the new dose. If you switch, change your medication in Steady so your reminders and level curve follow it.
Can Steady track both Wegovy and Zepbound?
Yes. Steady supports both, with each one’s own schedule, dose list and half-life.
Sources: Wegovy prescribing information (DailyMed), Zepbound prescribing information (DailyMed)