Free tool

Retatrutide dosage calculator

Enter your vial size and how much bacteriostatic water you added, then the target weekly dose in milligrams. The calculator returns the concentration and the exact draw on a U-100 syringe.

Reviewed for accuracy · Last reviewed July 7, 2026
Peptide amount
mg / vial
Bacteriostatic water
mL added
Target dose
mg / dose
Concentration5 mg/mL
Draw to80 units
on a 100-unit (1 mL) insulin syringe (example only)
Doses shown follow the once-weekly amounts studied in the Phase 2 trial (1 – 12 mg). Recalculate whenever your vial or water amount changes.

About these numbers

The example mixes a 10 mg vial with 2 mL of water, giving 5 mg/mL. At that concentration a 4 mg dose is 0.8 mL, or 80 units on a U-100 insulin syringe. Change any field and the draw updates.

Retatrutide is investigational: the once-weekly 1 mg, 4 mg, 8 mg, and 12 mg doses used here come from its published Phase 2 obesity trial, not from an approved label. It is not FDA-approved and there is no official prescribing dose.

References

  1. Triple-Hormone-Receptor Agonist Retatrutide for Obesity: A Phase 2 TrialNew England Journal of Medicine · 2023 · PMID 37366315 · DOI 10.1056/NEJMoa2301972
  2. A Phase 2 Study of Once-Weekly LY3437943 Compared With Placebo in Participants Who Have Obesity or Are Overweight With Weight-Related ComorbiditiesClinicalTrials.gov (sponsor: Eli Lilly and Company) · 2021 · NCT04881760
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This page is an independent educational reference and is not medical advice, and does not indicate any approval status for any use. Talk to a doctor before starting any compound.