Semaglutide vs Tirzepatide half-life
Semaglutide has an elimination half-life of about 6.9 days; Tirzepatide has about 5 days. Semaglutide is a GLP-1 receptor agonist; tirzepatide activates both GIP and GLP-1 receptors. Both have half-lives long enough for once-weekly dosing.
Side by side
| Semaglutide | Tirzepatide | |
|---|---|---|
| Half-life | 6.9 days (range 6–7 days) | 5 days |
| Route | SC weekly / oral daily | SC weekly |
| Category | GLP-1 & incretins | GLP-1 & incretins |
| Evidence | Clinical | Clinical |
| Remaining after 24 hours | 90.4% | 87.1% |
| Remaining after 7 days | 49.4% | 37.9% |
| ~97% cleared (5 half-lives) | 34.4 days | 25 days |
| Steady state (4-5 half-lives) | 27.5 days to 34.4 days | 20 days to 25 days |
Single-dose decay
Share of one dose remaining over time, assuming first-order elimination. Dashed lines mark each half-life.
Semaglutide (t½ 6.9 days) Tirzepatide (t½ 5 days)
Semaglutide: FDA label: elimination half-life of about 1 week. Tirzepatide: FDA label: half-life of about 5 days.
FAQ
Which lasts longer, Semaglutide or Tirzepatide?
Semaglutide lasts longer. Its half-life is about 6.9 days, versus 5 days for Tirzepatide, roughly 1.4 times longer.
How long do Semaglutide and Tirzepatide stay in your system?
With first-order elimination, about 97% of a single dose is cleared after five half-lives: roughly 34.4 days for Semaglutide and 25 days for Tirzepatide. Individual clearance varies.
How long until Semaglutide and Tirzepatide reach steady state?
With consistent repeated dosing, levels approach steady state after 4 to 5 half-lives: about 27.5 days to 34.4 days for Semaglutide, and 20 days to 25 days for Tirzepatide.
How reliable are these half-lives?
Semaglutide: Clinical evidence. Tirzepatide: Clinical evidence. Anecdotal values are community estimates and may be far off.