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 |
Rybelsus / Oral Wegovy Semaglutide (Oral) · Daily oral tablet | ~7 days | ~35 days | ~49 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.
Rybelsus / Oral Wegovy (Semaglutide (Oral))
Same molecule as injectable Wegovy — same half-life, same clearance. Key difference: must be taken fasted (30 min before food). FDA approved oral Wegovy for weight loss in December 2025.
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.
New: Oral Wegovy (December 2025)
The FDA approved the first oral GLP-1 for weight loss in December 2025 — semaglutide 50mg daily tablet. Same half-life and clearance as injectable, but very different absorption rules and a nearly flat daily drug level pattern.
Learn how oral GLP-1 works differently →Ozempic vs. Mounjaro — which is right for you?
Half-life is just one difference. See a full side-by-side: mechanism, weight loss data, side effects, and cost.
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.