GLP-1 Reference
How Long Do GLP-1 Medications Stay in Your System?
Half-life and clearance times for every major GLP-1 medication — based on published pharmacokinetic data from prescribing information and clinical studies.
| Medication | Half-life | 95% Cleared | 99% Cleared |
|---|---|---|---|
Ozempic / Wegovy Semaglutide SC · Weekly injection | 7 days | ~35 days | ~49 days |
Mounjaro / Zepbound Tirzepatide · Weekly injection | 5 days | ~25 days | ~35 days |
Trulicity Dulaglutide · Weekly injection | 5 days | ~25 days | ~35 days |
Victoza / Saxenda Liraglutide · Daily injection | ~13 hours | ~2.7 days | ~3.8 days |
Ozempic / Wegovy (Semaglutide SC)
Longest half-life of the weekly GLP-1s. Levels stay elevated for 4–6 weeks after stopping.
Mounjaro / Zepbound (Tirzepatide)
Dual GIP/GLP-1 agonist. Clears roughly 2 weeks faster than semaglutide.
Trulicity (Dulaglutide)
Same half-life as tirzepatide. Weekly dosing maintains stable therapeutic levels.
Victoza / Saxenda (Liraglutide)
Shortest half-life — must be taken daily. Clears the system within 4 days of stopping.
What does “half-life” mean?
A drug's half-life is the time it takes for the concentration in your body to fall by 50%. After one half-life, 50% remains. After two, 25%. After five half-lives, less than 4% remains — which is generally considered clinically cleared.
This is why Ozempic (7-day half-life) can still be detected weeks after the last dose, while liraglutide (13-hour half-life) is gone within days. Neither is “better” — it depends on your treatment goals and how your body responds.
Why does clearance time matter?
- • Missed doses: A drug with a long half-life loses less effect when you miss a dose. Semaglutide remains therapeutic even 4–5 days late.
- • Surgery or procedures: Some providers ask you to pause GLP-1s before procedures. Clearance time tells you how long that takes.
- • Switching medications: If you switch from one GLP-1 to another, knowing when the first drug has cleared avoids overlap.
- • Side effects: If you stop due to side effects, clearance time tells you roughly when symptoms from the drug should resolve.
See your exact drug level right now
The calculator uses pharmacokinetic modeling to show your estimated concentration at this moment — no account required.
Open the Drug Level Calculator →Clearance times are estimates based on published half-life data using the 5-half-life rule. Individual pharmacokinetics vary. Not medical advice.