Retatrutide 10 mg reconstitution calculator
How much bac water for retatrutide 10 mg?
There’s no single right amount: the water sets the strength, not how much retatrutide is in the vial, so use the volume on your pharmacy’s instructions. For example, 1 mL makes 10 mg/mL and 2 mL makes 5 mg/mL; the table below shows what each volume means on a U-100 syringe.
Your retatrutide vial
Syringe
1 mL · 2-unit marks
Work backwards
Find the water for a given reading in units.
Enter your numbers to see the result.
Enter your numbers
This is arithmetic, not medical advice. Confirm with your prescriber or pharmacist.
How our calculator worksAdvanced
Vial capacityOptional
The volume printed on the vial or its box, not the mg. We’ll tell you if the water won’t fit.
What each volume makes
| Water | Strength | Each unit | 1 mg is |
|---|---|---|---|
| 1 mL | 10 mg/mL | 100 mcg | 10 units |
| 2 mL | 5 mg/mL | 50 mcg | 20 units |
| 2.5 mL | 4 mg/mL | 40 mcg | 25 units |
Examples; use the volume on your pharmacy’s instructions. Units are on a U-100 syringe: 100 units = 1 mL.
About the 10 mg vial
Units only mean something next to your water
Units on a syringe measure volume, not drug. In a 10 mg vial, 1 mL of water makes each unit 100 mcg, 2 mL makes it 50 mcg and 2.5 mL makes it 40 mcg, so the same reading holds 2.5 times as much at 1 mL as at 2.5 mL. A number of units passed on from someone else’s vial, a video or a forum only matches yours if the vial size and the water are both the same. Start from the mg your prescriber gave you and the water you actually added, and let the calculator above work out the units.
What the bacteriostatic water adds
Bacteriostatic water is sterile water with 0.9% or 1.1% benzyl alcohol added as a preservative, and it comes in a multiple-dose container so repeated withdrawals can be made from it (the bacteriostatic water label). The same label says “NOT FOR USE IN NEONATES” and warns that some drugs may be incompatible with benzyl alcohol, advising you to consult a pharmacist. Retatrutide has no FDA label, so nothing official says whether it is compatible. The FDA’s August 2026 warning letter to a seller of “research use only” retatrutide also covered the bacteriostatic water it sold (FDA). Ask a pharmacist before you mix.
Who the FDA has warned about retatrutide
Any 10 mg retatrutide vial is outside the approved drug supply. The FDA says retatrutide cannot be used in compounding under federal law and is not a component of any FDA-approved drug. It has warned telehealth companies for marketing unapproved retatrutide, including directly to consumers; ingredient distributors for selling it to compounders; and outsourcing facilities for repackaging it (FDA). So a vial offered through a clinic, a compounder or a website can’t be a lawfully compounded product, whatever its label says. The calculator can still do the arithmetic for the mg printed on it, but nothing has checked that number.
Sources for these notes
- Bacteriostatic Water for Injection, USP: prescribing informationHospira, Inc., via DailyMed (U.S. National Library of Medicine), 2019 (opens in a new tab)
- Warning letter: TXP Innovations LLC dba Tex Peptides (MARCS-CMS 735067)U.S. Food and Drug Administration, 2026 (opens in a new tab)
- FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight LossU.S. Food and Drug Administration, 2026 (opens in a new tab)
About retatrutide
US regulatory status
Investigational, not approved
Retatrutide is not approved by the FDA for any use and has no brand name. Eli Lilly published phase 3 trials in 2026, but no FDA filing or approval had been announced as of October 16, 2026. The FDA says retatrutide cannot be used in compounding, and it has warned telehealth companies, ingredient distributors and websites selling “research use only” retatrutide.
As of
Sources (7)
- Novel Drug Approvals for 2026U.S. Food and Drug Administration, 2026 (opens in a new tab)
- Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of ObesityN Engl J Med, 2026 (opens in a new tab)
- Retatrutide in adults with obesity and type 2 diabetes (TRIUMPH-2): a double-blind, parallel-group, randomised, placebo-controlled, phase 3 trialLancet, 2026 (opens in a new tab)
- A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight (TRIUMPH-1), NCT05929066ClinicalTrials.gov, 2026 (opens in a new tab)
- FDA’s Concerns with Unapproved GLP-1 Drugs Used for Weight LossU.S. Food and Drug Administration, 2026 (opens in a new tab)
- Warning letter: Gram Peptides (MARCS-CMS 721806)U.S. Food and Drug Administration, 2026 (opens in a new tab)
- Warning letter: TXP Innovations LLC dba Tex Peptides (MARCS-CMS 735067)U.S. Food and Drug Administration, 2026 (opens in a new tab)
How this retatrutide calculator works
This retatrutide reconstitution calculator starts from the 10 mg in your vial. Add the water you mix it with and the dose your prescriber gave you; it divides the mg by the mL to get the strength, then turns your dose into mL and units on a 30, 50 or 100-unit syringe.
Peptinote never suggests a dose or a water volume. The example volumes are there to make the math easy to check, not as advice. For the full method, see the peptide calculator.
Questions people ask
How much bac water for a 10mg vial of retatrutide?
There’s no single right amount: use the volume on your pharmacy’s instructions. The water only sets the strength; the vial still holds 10 mg however much you add. With 1 mL it’s 10 mg/mL (100 mcg per unit), with 2 mL 5 mg/mL (50 mcg per unit) and with 2.5 mL 4 mg/mL (40 mcg per unit). Enter your volume and prescribed dose above to get the units. This product isn’t FDA-approved, so no official label sets a water volume and its contents aren’t verified.
How much bacteriostatic water do I mix with 10mg of retatrutide?
Whatever volume you add, only the strength changes; the vial still holds 10 mg. More water spreads it out, so each unit holds less and the same dose takes more units: easier to measure, but more liquid to inject. Going from 1 mL to 2.5 mL takes each unit from 100 mcg to 40 mcg. Check the volume on your pharmacy’s instructions first. This product isn’t FDA-approved, so no official label sets a water volume and its contents aren’t verified.
How much bacteriostatic water do I add to retatrutide?
Use the volume your pharmacy specifies, and never more than the vial itself can hold (its size in mL, not the 10 mg on the label). If you weren’t given a volume, ask a pharmacist before mixing. For reference, the bac water calculator shows the arithmetic: water (mL) = vial mg × units ÷ (dose mg × 100). This product isn’t FDA-approved, so no official label sets a water volume and its contents aren’t verified.
How many units of bac water for 10mg retatrutide?
Bac water is measured in mL, and on a U-100 insulin syringe 1 mL is 100 units. So 1 mL is 100 units, 2 mL is 200 units and 2.5 mL is 250 units: more than one 100-unit syringe holds once you pass 1 mL. Ask your pharmacist which syringe to use for adding the water. The amount itself comes from your pharmacy’s instructions; the table above shows what each volume gives. This product isn’t FDA-approved, so no official label sets a water volume and its contents aren’t verified.
How do I reconstitute 10 mg of retatrutide?
Wipe both stoppers with alcohol and let them dry. Draw the volume of bacteriostatic water your pharmacy specifies into a new syringe, add it slowly down the inside of the vial, then swirl gently until clear; don’t shake. Label it with the strength: 10 mg in 1 mL is 10 mg/mL. Full steps: how to reconstitute peptides.
How do I mix a retatrutide injection?
Mixing your retatrutide 10 mg vial takes the bacteriostatic water your pharmacy specifies and a new sterile syringe. Add the water slowly against the glass and swirl, never shake, until the liquid is clear. If it stays cloudy or has particles, don’t use it; call your pharmacy. Then write the strength and date on the vial and store it as the label says (how to store peptides).
Is there a peptide calculator for retatrutide?
This page is the retatrutide 10 mg reconstitution calculator. Enter the water you add (or tap an example volume) and your prescribed dose, and it shows the units to draw on a 30, 50 or 100-unit syringe, the strength, and the doses in the vial, with every step of the math. It never suggests a dose.
How do retatrutide units convert to mg?
Units measure volume (1 unit = 0.01 mL), so converting them to mg needs the strength: mg = units ÷ 100 × mg/mL. In a 10 mg vial, with 1 mL each unit holds 100 mcg, with 2 mL each unit holds 50 mcg and with 2.5 mL each unit holds 40 mcg. Multiply by the units you draw, or let the calculator above do it, with every step shown.
Can Peptinote tell me how many units to take?
No. Peptinote never suggests a dose. Enter the dose your prescriber gave you, and the calculator shows how to measure it: the units, the mL and where the line sits on your syringe, with every step of the math. If you aren’t sure what your dose is, ask your prescriber or pharmacist before drawing anything. How our calculator works.
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Every result is plain arithmetic from formulas we publish in full and check with automated tests. Peptinote doesn’t suggest doses and never sells or links to sellers of peptides.