Tirzepatide vs Retatrutide
This is the 'next-generation' comparison people search when they've heard about triple agonists. The honest framing is that these aren't on the same footing — tirzepatide is approved and widely used, retatrutide is investigational.
Side by side
| Tirzepatide | Retatrutide | |
|---|---|---|
| Class | GLP-1 & incretins | GLP-1 & incretins |
| Form | Injection | Injection |
| Half-life | ≈ 5 days (120 h) | ≈ 6 days (144 h) |
| Storage | — | — |
| Dose units | mg, ml | mg, ml |
| FDA status | Approved | Not FDA-approved |
Facts from the Stack compound library. See the full pages: Tirzepatide · Retatrutide.
How they differ
Receptor coverage
Tirzepatide hits two receptors (GIP + GLP-1). Retatrutide is a triple agonist — GIP, GLP-1 and glucagon. The glucagon arm is the new ingredient and the reason it's studied separately.
Approval status
Tirzepatide is FDA-approved. Retatrutide is investigational — in clinical trials, not approved for any use. The library labels this plainly on each page.
Cadence
Both are weekly injectables under study/use with multi-day half-lives, so both fit the weekly-reminder + titration-log pattern.
Why it matters for tracking
For anything investigational, the value of a meticulous log goes up, not down — dose, date and any noted effects are the record you'd actually want later.
Tracking either one
Whichever you log, the workflow is the same in Stack: add it once, set the schedule, and let the app handle reminders, supply projection and an "in your system" curve from the half-life. Run both? Group them into one protocol you can pause together.
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Get the appLast reviewed 2026-06-11