GLP-1 half-lives compared
In short
A half-life is the time the body takes to clear half of a medicine. Among the 8 FDA-approved GLP-1 medicines it runs from about 3 hours for lixisenatide to about 7 days for semaglutide. After 5 half-lives about 3% is left, because halving five times leaves 1/32.
| Medicine | Half-life | 5 half-lives (about 3% left) | Details | Source |
|---|---|---|---|---|
| Lixisenatide (Adlyxin) | ~3 hours | ~15 hours | About 3 hours. Levels peak 1–3.5 hours after a shot. | PubMed |
| Liraglutide (Victoza, Saxenda) | ~13 hours | ~3 days | About 13 hours. Levels peak 8–12 hours after a shot, which is why it's a daily medicine. | DailyMed |
| Orforglipron (Foundayo) | ~39 hours | ~8 days | About 29 to 49 hours, so it builds to a steady level after about a week of daily pills. Levels peak 4 to 8 hours after a dose. About 77% of a dose is absorbed, and food lowers that only a little. | DailyMed |
| Tirzepatide (Mounjaro, Zepbound) | ~5 days | ~25 days | About 5 days. Levels peak 8–72 hours after a shot and reach a steady level after about 4 weeks of weekly shots. | DailyMed |
| Dulaglutide (Trulicity) | ~5 days | ~25 days | About 5 days. Levels peak 1–3 days after a shot and level out after 2–4 weeks of weekly shots. | DailyMed |
| Semaglutide (Ozempic, Wegovy) | ~7 days | ~35 days | About 7 days, so weekly shots build to a steady level after 4–5 weeks. Levels peak 1–3 days after a shot. The daily pill peaks about an hour after taking it. | DailyMed |
| Oral semaglutide (Rybelsus, Wegovy pill) | ~7 days | ~35 days | About 7 days, like the shots, so daily pills build to a steady level over 4 to 5 weeks. Levels peak about an hour after each tablet. | DailyMed |
| Exenatide (Byetta, Bydureon) | Varies | Varies by product | Twice-daily Byetta: about 2.4 hours, peaking about 2 hours after a shot. The weekly version releases slowly from tiny beads, so levels build over several weeks. | DailyMed |
Half-lives are averages from each drug's label or trials and vary from person to person. Investigational GLP-1 drugs aren't FDA-approved and aren't listed here.
