Retatrutide Dosage Calculator & Research Doses

1Set Up Your Mix

20 mg/mL · 20000 mcg/mL

1. Pick your peptide

2. How much peptide is in the vial? It's printed on the label — usually something like 5 mg

3. How much water are you adding? More water makes each dose easier to measure

4. How much do you want per dose?

All answers assume a standard 1 mL U-100 syringe, where 1 unit = 0.01 mL. That is the usual insulin syringe and the one every number here is based on.

Your Answer — RetatrutideYour Answer

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20Draw To This Line

0.2That's This Many mL

5Doses In The Vial

20 mg ÷ 1 mL = 20 mg/mL → 4 mg ÷ 20 mg/mL = 0.2 mL → × 100 = 20 units—

Looks good. Draw to 20 units on a 1 mL syringe. That is an easy amount to measure, and this vial gives you 5 doses.

2Week-By-Week Plan — Retatrutide

Phase 2 dose escalation

When	Dose	How Often	How Many mL	Draw To	Number Of Doses
Phase 2 low arm	1 mg	once weekly	0.05 mL	5 u	20 doses
Phase 2 arm	4 mg	once weekly	0.2 mL	20 u	5 doses
Phase 2 arm	8 mg	once weekly	0.4 mL	40 u	2 doses
Phase 2 top arm	12 mg	once weekly	0.6 mL	60 u	1 doses

Weeks until the top dose

12 weeks

Peptide used getting there

52 mg

Vials you'll need

3 × 20 mg

Once you're at the top dose

48 mg / 4 wk · 2.4 vials

Where this plan came from

A clinical trial schedule

Where this came from: Jastreboff AM, et al. New England Journal of Medicine, 2023 — phase 2 dose-escalation study. The trial ran several arms (1, 4, 8 and 12 mg) and escalated gradually in four-week steps. The path below runs to the highest arm; exact per-arm schedules are in the published protocol. View the source protocol ↗

3Common Doses — Retatrutide

worked out for your mix

Level	Dose	How Often	How Many mL	Draw To	Doses In Vial
Weeks 1–4	1 mg	once weekly	0.05 mL	5 u	4	4 mg
Weeks 5–8	4 mg	once weekly	0.2 mL	20 u	4	16 mg
Weeks 9–12	8 mg	once weekly	0.4 mL	40 u	4	32 mg
Week 13 onward per 4 weeks from here on	12 mg	once weekly	0.6 mL	60 u	4	48 mg

Please read this. These numbers come from published research. They are here as reference, not as instructions. A lot of them come from lab studies rather than studies in people, and some of these peptides have never been given to a person at all.

About RetatrutideAbout This Peptide

Metabolic / Incretin

Also known as

LY3437943, triple GIP/GLP-1/glucagon agonist

Class

Metabolic / Incretin

Route

Subcutaneous

Half-life

~6 days

Evidence tier

Clinical

A triple-receptor agonist in ongoing phase 3 development. Phase 2 data reported dose-dependent weight reduction up to 12 mg weekly. Not approved anywhere; long-term safety is not established.

Buy Retatrutidethis peptide

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Where These Numbers Come From

Clinical — Human trial or approved-label dosing published

Triple-hormone-receptor agonist retatrutide for obesity — a phase 2 trial Jastreboff AM, et al. New England Journal of Medicine, 2023

The dose-ranging trial that produced the 1/4/8/12 mg arms cited everywhere.

Find on PubMed ↗

Retatrutide in type 2 diabetes — phase 2 randomised trial Rosenstock J, et al. The Lancet, 2023

Parallel diabetes dose-ranging data.

Find on PubMed ↗

Newest Studies — —

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Not reviewed by us. This list is pulled straight from Europe PMC as papers are published. Nobody has checked whether these are any good, or whether they change anything above. The dose numbers on this page only ever change after a person reviews the evidence.

Research Use Only — Confirm to Continue

Retatrutide Dosage & Reconstitution

1Set Up Your Mix

Your Answer — RetatrutideYour Answer

2Week-By-Week Plan — Retatrutide

3Common Doses — Retatrutide

About RetatrutideAbout This Peptide

Where These Numbers Come From

Newest Studies — —

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