The Last Peptide

← All peptides

Metabolic & Weight Management

Retatrutide + Tirzepatide calculator

An unstandardized supplier blend of retatrutide and tirzepatide. No such combined product is approved or studied.

Also known as: Triple + dual agonist blend

FDA status — not an approved drug Not FDA-approved. Tirzepatide is approved as a single agent (Mounjaro, Zepbound), but retatrutide is investigational, and no combination of the two is approved or studied.

400 units
on a 100-unit syringe
4 mL
volume drawn
1 mg/mL
concentration
2 doses
per vial
050100

This draw does not fit the selected syringe.400 units exceeds the 100-unit barrel. Choose a larger syringe, use less bacteriostatic water, or split the dose.

Schedule Retatrutide + Tirzepatide → Set your dosing schedule and get a phone notification when each dose is due. Free.

A worked example

A 10 mg vial reconstituted with 10 mL of bacteriostatic water gives 1 mg/mL. A 4000 mcg dose is then 4 mL — about 400 units on a 100-unit insulin syringe, giving roughly 2 doses per vial before accounting for residual volume left in the vial and syringe.

Prefer paper? Download the printable Retatrutide + Tirzepatide dosing chart (PDF) — every vial size and water volume in syringe units, with the same review byline as this page. All charts →

Commonly cited dose range

Figures circulating for Retatrutide + Tirzepatide run from 2400 mcg to 12000 mcg. This is an unstandardized compounded blend with no established dosing. Figures shown are reference points only and do not describe a studied regimen. Combining two incretin-class agonists has no clinical evidence base.

Read this as reference information, not instruction. These numbers describe what is commonly discussed, not what is right for any individual. Dose, frequency, and whether to use Retatrutide + Tirzepatide at all are decisions for a licensed clinician who knows your history.

Common questions

Is there an approved retatrutide-tirzepatide combination?

No. Tirzepatide is approved as a single agent; retatrutide is investigational. No trial has studied combining them, and blends sold by suppliers are unregulated and unstandardized.

Why would someone combine them?

There is no clinical rationale supported by evidence — both are incretin-class agonists with overlapping GLP-1 activity. Combining them is an unregulated practice without trial support.

Other calculators