August 29, 2026
RESEARCH USE ONLY. This page contains unit-conversion arithmetic only. It is not a dosing guide, not a protocol, and not a preparation or administration instruction for any person or animal. Products discussed on this site are supplied strictly for laboratory and research purposes.
Retatrutide is supplied in eight vial sizes, which is more than any other compound in our catalogue. The tables below convert vial mass and solvent volume into concentration — nothing more. Choosing a volume is a measurement decision, not a protocol.
Sourced fact: FDA states that “Retatrutide and cagrilintide cannot be used in compounding under federal law. Additionally, these are not components of FDA-approved drugs and have not been found safe and effective for any condition.” [2]
Sourced fact: The same FDA page states the agency has “warned companies that have illegally sold unapproved drugs containing semaglutide, tirzepatide or retatrutide that are falsely labeled ‘for research purposes’ or ‘not for human consumption’” where the products “have been sold directly to consumers for human use with dosing instructions.” [2]
Inference: We are quoting that warning rather than working around it. This page contains no dosing instructions, no protocol, and no recommendation of any volume. It converts milligrams and millilitres into concentration, which is arithmetic that applies identically to any solute. If you are looking for a dosing schedule, this page does not contain one and we will not supply one.
Read down to your vial mass, across to the volume of bacteriostatic water added. The cell is the resulting concentration.
| Vial | 1 mL | 2 mL | 3 mL | 5 mL |
|---|---|---|---|---|
| 5 mg | 5 mg/mL | 2.5 mg/mL | 1.67 mg/mL | 1 mg/mL |
| 10 mg | 10 mg/mL | 5 mg/mL | 3.33 mg/mL | 2 mg/mL |
| 15 mg | 15 mg/mL | 7.5 mg/mL | 5 mg/mL | 3 mg/mL |
| 20 mg | 20 mg/mL | 10 mg/mL | 6.67 mg/mL | 4 mg/mL |
| 30 mg | 30 mg/mL | 15 mg/mL | 10 mg/mL | 6 mg/mL |
| 40 mg | 40 mg/mL | 20 mg/mL | 13.3 mg/mL | 8 mg/mL |
| 50 mg | 50 mg/mL | 25 mg/mL | 16.7 mg/mL | 10 mg/mL |
| 60 mg | 60 mg/mL | 30 mg/mL | 20 mg/mL | 12 mg/mL |
Twenty units on an insulin syringe is 0.2 mL. The same grid, expressed as mass rather than concentration.
| Vial | 1 mL | 2 mL | 3 mL | 5 mL |
|---|---|---|---|---|
| 5 mg | 1 mg | 0.5 mg | 0.333 mg | 0.2 mg |
| 10 mg | 2 mg | 1 mg | 0.667 mg | 0.4 mg |
| 15 mg | 3 mg | 1.5 mg | 1 mg | 0.6 mg |
| 20 mg | 4 mg | 2 mg | 1.33 mg | 0.8 mg |
| 30 mg | 6 mg | 3 mg | 2 mg | 1.2 mg |
| 40 mg | 8 mg | 4 mg | 2.67 mg | 1.6 mg |
| 50 mg | 10 mg | 5 mg | 3.33 mg | 2 mg |
| 60 mg | 12 mg | 6 mg | 4 mg | 2.4 mg |
Worked example: a 20 mg vial reconstituted with 2 mL gives 10 mg/mL. Twenty units is 0.2 mL. 0.2 mL × 10 mg/mL = 2 mg.
An insulin syringe is graduated in units, which are a volume marking, not a mass. On both U-100 and U-50 insulin syringes, one unit corresponds to 0.01 mL. The difference is barrel capacity and gradation spacing — not the unit-to-volume relationship. A U-50 holds 0.5 mL across 50 units; a U-100 holds 1.0 mL across 100 units. Both are 100 units per millilitre.
The arithmetic is: mass = (peptide mg ÷ mL of solvent added) × (units × 0.01)
Our reconstitution calculator runs this across a 44-compound library if you would rather not do it by hand.
Sourced fact: The Bacteriostatic Water for Injection label directs: “Do not store reconstituted solutions of drugs for injection unless otherwise directed by the manufacturer of the solute.” The same label describes the product as supplied in “a multiple-dose container from which repeated withdrawals may be made to dilute or dissolve drugs for injection,” preserved with 0.9% or 1.1% benzyl alcohol. [1]
Inference: The widely-quoted 28-day figure describes the multiple-dose container of water, not what you dissolved in it. We traced that rule to its actual source — it is not printed on the FDA label at all — in where the 28-day rule actually comes from.
This is unit-conversion arithmetic for laboratory research planning. It is not medical or veterinary advice, not a protocol, not a recommendation of any volume, and not an instruction to administer anything to any person or animal. Retatrutide is not approved by the FDA for human or veterinary use, and FDA states it is not a component of any FDA-approved drug. [2]
Reconstitution arithmetic for every compound in the catalogue: BPC-157 · TB-500 · Wolverine Stack · GLOW · KLOW · CJC-1295 / Ipamorelin · Ipamorelin · CJC-1295 No DAC · GHK-Cu · Epitalon · MOTS-c · AOD-9604 · NAD+ · PT-141 · Tesamorelin · Retatrutide · Tirzepatide · SS-31 · Selank · Semax · KPV · DSIP · PEG-MGF · FOXO4-DRI · ARA-290 · 5-Amino-1MQ
Retatrutide · Bacteriostatic Water, USP · Reconstitution calculator · Reconstitution handling guide · Is retatrutide FDA approved? · How retatrutide works · Retatrutide vs tirzepatide
BPC-157 is currently the only compound in our catalogue with completed third-party COA figures published on its page — lot 3CDMQXU, chromatographic purity >99.95%, 99.2% of stated label claim, identity confirmed by HPLC-UV-MS, tested by Krause Analytical. Every other product page, including this one, states plainly that its certificate is pending.
RESEARCH USE ONLY — FULL DISCLAIMER. The products discussed on this page are supplied strictly for laboratory and scientific research purposes. They are not for human or veterinary use, and not for consumption. These statements have not been evaluated by the Food and Drug Administration. Nothing on this page is intended to diagnose, treat, cure, or prevent any disease in humans or animals. Nothing here constitutes medical or veterinary advice or a dosing, preparation, or administration recommendation for any person or animal.
