Tools / Time in system
How long do peptides and GLP-1s stay in your system?
Pick your medicine and the date of your last dose. You'll see roughly how much is left over time and when it's mostly out of your system.
Rule of thumb: after 5 half-lives about 3% of a dose is left. Semaglutide ≈ 5 weeks, tirzepatide ≈ 25 days.
Half-lives come from each medicine's label. For anything else, enter a half-life yourself.
Ozempic, Wegovy, Rybelsus. Half-life about 1 week.
Pick the date of the last injection or tablet.
Semaglutide is mostly out of your system after
35days
5 half-lives after the last dose, when about 3% is left. Pick the date of your last dose to see the calendar date.
Checked 8 November 2026 by the PeptideTracker editorial team · This tool does the math only. It doesn't recommend a dose.
[02] Half-lives
Half-lives from the labels
| Medicine | Half-life | Mostly cleared (5 half-lives) | Source |
|---|---|---|---|
| Semaglutide (Ozempic, Wegovy, Rybelsus) | about 1 week | about 35 days | Label |
| Tirzepatide (Mounjaro, Zepbound) | about 5 days | about 25 days | Label |
| Dulaglutide (Trulicity) | about 5 days | about 25 days | Label |
| Liraglutide (Saxenda, Victoza) | about 13 hours | about 65 hours | Label |
Half-lives are averages from each medicine's US prescribing information, section 12.3. Your own may differ.
[03] Research peptides
Why there's no preset for BPC-157 or TB-500
Research peptides haven't been through the trials that measure half-life in people. Numbers you'll see online usually come from animal studies or guesses. If you have a figure from a study you trust, choose “Something else” and enter it.
[04] Questions
Questions
How long does semaglutide stay in your system?
Semaglutide's half-life is about 1 week, so after 5 half-lives, roughly 5 weeks after the last dose, about 3% is left. Most people treat that as mostly out of the system.
How long does tirzepatide stay in your system?
Tirzepatide's half-life is about 5 days. After 5 half-lives, roughly 25 days after the last dose, about 3% is left.
How long do peptides stay in your system?
About 5 half-lives, when roughly 3% of a dose is left. From the labels that's about 5 weeks for semaglutide, about 25 days for tirzepatide and dulaglutide, and about 3 days for liraglutide. BPC-157 and TB-500 have no measured half-life in people, so nobody can give a real figure.
Why five half-lives?
After each half-life, half of what's left is gone. After 5, about 3% of a dose remains, which is the usual rule of thumb for mostly cleared.
Is this the same as how long it shows up on a test?
No. Tests look for different things at different levels. This only estimates how much of a dose is left in the body.
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[05] Read next
Guides that go with this calculator
- Peptide half-life chartHalf-life is how long it takes for half a dose to leave your blood. Every figure below names its source and says whether it was measured in people or only in animals.
- Missed a GLP-1 dose? The rule for each medicineHow late is too late depends on your medicine. Each US label sets its own window, and a few UK rules differ.
- TirzepatideTirzepatide is a once-weekly injection sold as Mounjaro and Zepbound. Label doses run from 2.5 mg up to 15 mg. Compounded vials are not FDA-approved.
- SemaglutideSemaglutide label doses: Ozempic 0.25 mg to 2 mg weekly, Wegovy 0.25 mg to 2.4 mg (max 7.2 mg). Half-life about 1 week. 0.25 mg at 2.5 mg/mL is 10 units.
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