PepDialed

Reference · cited facts

Retatrutide

LY3437943Half-life ≈6 daysResearch use · not FDA-approvedReviewed July 2026

Educational information and a math tool only — not medical advice, a dose recommendation, or an endorsement of peptide use. Not FDA-approved for human use. Consult a licensed healthcare provider before starting, stopping, or changing anything.

Class / mechanism
Retatrutide is an investigational triple agonist (GIP / GLP-1 / glucagon receptors) being studied by Eli Lilly.
SOURCE [1]
Regulatory status
Not FDA-approved. Investigational — in Eli Lilly Phase 3 trials (TRIUMPH programme) as of July 2026.
FDA · July 2026
Reported half-life
≈6 days
PUBMED
Human evidence
Limited human data
LITERATURE

What the literature reports

  • Retatrutide is an investigational triple agonist (GIP / GLP-1 / glucagon receptors) being studied by Eli Lilly.
  • A published Phase 2 trial reported an elimination half-life of approximately 6 days (once-weekly dosing was used in the study).
  • It is not approved by the FDA for any use and is not available as a prescription product; Phase 3 outcomes trials are ongoing.

Honest caveats

  • No FDA-approved product exists — human safety and efficacy are still being established in Phase 3.
  • Any vial sold as “research use only” is not a medicine and has no approved dosing.

Reconstitution calculator

Enter your own vial size, BAC water and target dose — get exact syringe units.

Open Retatrutide calculator

Sources

  1. [1] NEJM 2023 — Phase 2 trial (NEJMoa2301972)
  2. [2] PMC11271400 — pharmacology review