How long does semaglutide stay in your system?
About 5 weeks after your last dose. Semaglutide's half-life is roughly 1 week, and a medication is treated as practically cleared after five half-lives, the point where about 97% has been eliminated. For tirzepatide, with a half-life near 5 days, that works out to about 25 days. Liraglutide, at 13 hours, is gone in under 3 days.
By compound
| Compound | Half-life | Practically cleared after |
|---|---|---|
| Tirzepatide | 5 days (120 hours) | 25 days (600 hours) |
| Semaglutide (injectable) | 7 days (168 hours) | 35 days (840 hours) |
| Semaglutide (oral) | 7 days (168 hours) | 35 days (840 hours) |
| Liraglutide | 13 hours | 2.7 days (65 hours) |
| Dulaglutide | 5 days (120 hours) | 25 days (600 hours) |
| Exenatide (immediate release) | 2.4 hours | 12 hours |
| Retatrutide | 6 days (144 hours) | 30 days (720 hours) |
| Survodutide | 6 days (144 hours) | 30 days (720 hours) |
| Cagrilintide | 7.5 days (180 hours) | 37.5 days (900 hours) |
| Orforglipron | 40 hours | 8.3 days (200 hours) |
| Tesamorelin | 30 minutes | 3 hours |
| PT-141 (Bremelanotide) | 2.7 hours | 14 hours |
| MK-677 (Ibutamoren) | 24 hours | 5 days (120 hours) |
| Sermorelin | 12 minutes | 1 hours |
Only compounds with an FDA label or published human PK study are listed here. The full chart includes research peptides with weaker evidence, flagged as such.
Why five half-lives
Elimination is proportional, not linear. Each half-life removes half of what is left: 50% gone after one, 75% after two, 87.5% after three, 94% after four, about 97% after five. Past that the remainder is too small to matter clinically, which is why five half-lives is the standard convention for "out of your system."
The same arithmetic runs in reverse when you start. Levels climb until intake and elimination balance, which also takes four to five half-lives, so weekly semaglutide reaches steady state after roughly 4 to 5 weeks of dosing rather than on the first injection.
Cleared is not the same as no longer working
Blood concentration and felt effect are different curves. Appetite suppression usually fades as levels drop, but the timing varies between people and is not something a half-life table can predict. Kidney function, liver function and body weight all shift real clearance away from the population average.
See your own levels
Bo takes your actual logged doses and models what is still in your system today, using these same FDA-sourced constants.
Educational information only. Bo is a tracking app, not a medical device, and nothing here is medical advice, a dosing recommendation, or a substitute for your prescriber. Half-lives are population averages from the sources cited on each row; individual clearance varies with body weight, kidney and liver function, and other medication.