Retatrutide Reconstitution Reference
Retatrutide Reconstitution Chart: Every Vial, Every Dose
This is the retatrutide reconstitution chart to screenshot before your next injection. It crosses every common vial size (5mg through 60mg) with the recommended bacteriostatic water volume and converts each titration dose into the exact units you draw on a U-100 insulin syringe. No algebra, no calculator needed. Find your row, pick your dose column, and read the number. If you want the actual mixing procedure instead, the step-by-step reconstitution guide covers sterile technique and equipment.
Key Takeaways
- One chart covers everything: the retatrutide reconstitution chart below maps all six common vial sizes against every dose from 0.5mg to 12mg, in insulin syringe units.
- The 10mg + 2mL setup is the standard: it gives a clean 5mg/mL where 1mg = 20 units, 2mg = 40, 4mg = 80, 8mg = 160.
- Units depend on concentration, not just dose: the same 2mg dose is 40 units at 5mg/mL but only 20 units at 10mg/mL.
- Watch syringe capacity: a standard 1mL U-100 syringe holds 100 units. Any draw above that needs a larger syringe or a split.
- For the actual mixing steps, use the step-by-step reconstitution guide; this page is the lookup table only.
6 vial sizes
5, 10, 15, 20, 30, 60 mg
5mg/mL
10mg vial + 2mL BAC water
100 units
Max in a 1mL U-100 syringe
28-60 days
Refrigerated stability
What This Retatrutide Reconstitution Chart Does
This is a fast lookup table, not a procedure article. Find your vial size and BAC water volume in the left column. Read across to your dose column for the exact units to draw on a U-100 insulin syringe. No math. If you need the mixing procedure itself, the step-by-step reconstitution guide covers sterile technique, equipment, and the mixing sequence. The retatrutide hub links the rest of the cluster.
Investigational Status Notice
Retatrutide is investigational. It is not FDA approved as of 2026 and is in Phase 3 trials for obesity. It is not available as a finished pharmaceutical product. The FDA states retatrutide cannot be used in compounding under federal law, so compounding pharmacies cannot lawfully supply it. In the US, lawful access is limited to a clinical trial or Lilly's expanded access program (ClinicalTrials.gov NCT07629401), which a doctor must request, for adults with a BMI of 35 or more whose obesity has not responded to the highest available dose of current weight-loss treatment, who have two or more serious obesity-related complications, and who cannot join a trial; see compounded retatrutide for the details. This chart is for informational purposes only and does not replace professional medical advice. Consult a healthcare professional before any use.
Quick Answer: 10mg Vial + 2mL BAC Water
The most common vial setup for retatrutide is a 10mg vial with 2mL of bacteriostatic water, which gives a 5mg/mL concentration. Here are the standard titration doses for that single setup, including the 0.5mg and 1mg points that microdosing users draw.
| Dose (10mg vial, 2mL, 5mg/mL) | Units on a U-100 syringe |
|---|---|
| 0.5mg (microdose) | 10 units |
| 1mg | 20 units |
| 2mg (standard start) | 40 units |
| 4mg | 80 units |
| 8mg | 160 units † |
At 5mg/mL the 2mg starting dose is a clean 40 units, and every standard step up to 4mg stays within a single 1mL syringe. The 8mg dose reads 160 units (†), which exceeds a standard syringe and needs a split draw or a larger syringe. The full titration runs 2mg, then 4mg, then 8mg, then 12mg at four-week intervals.
Need a Dose That Is Not in the Chart?
The chart covers every standard setup. For a custom vial size or a non-standard BAC water volume, the free calculator does the math instantly.
Open the free retatrutide calculator →How the Retatrutide Unit Math Works
Every cell in this chart comes from one formula: units = (desired dose in mg divided by concentration in mg per mL) times 100. Concentration is your vial size divided by the BAC water volume you added. For the standard 10mg vial with 2mL of water, concentration is 10 divided by 2, or 5mg/mL. A 2mg dose is then (2 / 5) times 100 = 40 units on a U-100 syringe, where 100 units equals exactly 1mL.
The retatrutide unit formula: vial size and water volume set the concentration, then dose divided by concentration times 100 gives units.
Why units matter: the unit value depends on concentration, not just the dose. The same 2mg dose is 40 units at 5mg/mL but only 20 units at 10mg/mL. Reading the wrong concentration's number is the most common dosing error here, so this chart lists the concentration on every row. The retatrutide dosing in units page goes deeper on this conversion.
Master Retatrutide Reconstitution Chart (All Vial Sizes)
This is the master table. Each row is a vial size paired with a common BAC water volume and the concentration that produces. Each column is a titration dose, from the 0.5mg microdose through the 12mg ceiling. The cell value is the units you draw on a standard U-100 insulin syringe. The starred rows (10mg + 2mL and 30mg + 3mL) are the most common vial setups.
| Vial / BAC water | Conc. | 0.5mg | 1mg | 2mg | 4mg | 8mg | 12mg |
|---|---|---|---|---|---|---|---|
| 5mg + 1mL | 5mg/mL | 10 | 20 | 40 | 80 | n/a | n/a |
| ★ 10mg + 2mL | 5mg/mL | 10 | 20 | 40 | 80 | 160 † | n/a |
| 10mg + 1mL | 10mg/mL | 5 | 10 | 20 | 40 | 80 | n/a |
| 15mg + 3mL | 5mg/mL | 10 | 20 | 40 | 80 | 160 † | 240 † |
| 15mg + 1.5mL | 10mg/mL | 5 | 10 | 20 | 40 | 80 | 120 † |
| 20mg + 4mL | 5mg/mL | 10 | 20 | 40 | 80 | 160 † | 240 † |
| 20mg + 2mL | 10mg/mL | 5 | 10 | 20 | 40 | 80 | 120 † |
| ★ 30mg + 3mL | 10mg/mL | 5 | 10 | 20 | 40 | 80 | 120 † |
| 60mg + 6mL | 10mg/mL | 5 | 10 | 20 | 40 | 80 | 120 † |
† Exceeds standard 1mL U-100 syringe capacity. Use a 1.5mL or 3mL syringe, or split into two equal draws. See the Syringe Capacity Guide section below. All values calculated using units = (dose_mg / concentration_mg_per_mL) x 100, drawn on a U-100 insulin syringe where 100 units equals 1mL. n/a means the requested dose exceeds the total amount of retatrutide in the vial, a physically impossible draw at any concentration. A value over 100 units is a real, drawable dose; it just cannot fit one standard 1mL syringe.
How to Read This Chart
Find the row that matches your vial size and how much BAC water you added. Move across to the column for the dose your protocol calls for this week. The number in that cell is the mark you draw to on a U-100 insulin syringe. If your exact vial and water combination is not listed, run it through the free retatrutide calculator for the precise units.
Starred Row Callout: The Standard Retatrutide Setup
The most common vial setup for retatrutide is a 10mg vial with 2mL of BAC water. That gives 5mg/mL, where the early titration doses land on clean, round numbers: 0.5mg = 10 units, 1mg = 20 units, 2mg = 40 units, 4mg = 80 units, 8mg = 160 units. The 8mg dose at this concentration exceeds a standard 1mL syringe and needs a split draw or a 1.5mL syringe. For the larger 30mg vial, 3mL of BAC water gives 10mg/mL, where 2mg = 20 units, 4mg = 40, 8mg = 80, and 12mg = 120 units (a split draw or larger syringe). Always confirm against the formula, not from memory.
Syringe Capacity Guide
A standard 1mL U-100 insulin syringe holds a maximum of 100 units. When a dose maps to more than 100 units you have exceeded the syringe and need a 1.5mL syringe, a 3mL syringe, or a split draw across two injections. Concentration decides where that ceiling lands.
The syringe ceiling depends on concentration: at 5mg/mL it lands at a 5mg dose, at 10mg/mL it lands at a 10mg dose.
| Concentration | Dose at the 100-unit ceiling | Above this, use |
|---|---|---|
| 5mg/mL | 5mg = 100 units | 1.5mL or 3mL syringe, or split draw |
| 10mg/mL | 10mg = 100 units | 1.5mL or 3mL syringe, or split draw |
When a dose lands above the ceiling, your options are a 1.5mL syringe, a 3mL syringe, or splitting the dose into two equal injections at separate sites. For injection technique and how to split a draw cleanly, see the step-by-step reconstitution guide.
Retatrutide Reconstitution Chart by Vial Size
The master table compresses everything into one grid. This section unpacks each vial size so you can see which one fits your protocol. For the actual mixing procedure, sterile technique, and equipment list, see the step-by-step reconstitution guide.
5mg Vial
A 5mg vial with 1mL of BAC water gives 5mg/mL. It covers 0.5mg (10 units), 1mg (20 units), 2mg (40 units), and 4mg (80 units), all within a single 1mL syringe. It cannot cover an 8mg or 12mg dose because the vial holds only 5mg total. This is a trial or microdosing size: a 5mg vial holds two and a half 2mg starting doses, so most people move to a larger vial once they tolerate treatment.
10mg Vial (Most Common)
The default. With 2mL of BAC water it gives 5mg/mL: 0.5mg = 10 units, 1mg = 20, 2mg = 40, 4mg = 80, and 8mg = 160 units (a split draw or larger syringe). For higher doses some users add 1mL of water instead, giving 10mg/mL, where 2mg = 20 units, 4mg = 40, and 8mg = 80, keeping every step inside one syringe. A 12mg dose still exceeds a 10mg vial at any concentration. Most reconstitution instructions default to this size because it carries the early titration cleanly.
15mg Vial
A 15mg vial with 3mL of BAC water gives 5mg/mL: 2mg = 40 units, 4mg = 80, 8mg = 160 units, and 12mg = 240 units. The 8mg and 12mg draws exceed a 1mL syringe and need a split or a larger syringe. Using 1.5mL of water instead gives 10mg/mL, which brings the 12mg dose down to 120 units. This size suits someone who wants the full titration in reach without a 30mg vial.
20mg Vial
A 20mg vial with 4mL of BAC water gives 5mg/mL with the same pattern as the 15mg setup, plus more total doses per vial. With 2mL of water it gives a concentrated 10mg/mL, where 2mg = 20 units, 4mg = 40, 8mg = 80, and 12mg = 120 units. The concentrated option keeps draw volumes small, which suits anyone who finds large-volume draws awkward. The trade-off is that a small reading error maps to a larger error in milligrams.
30mg Vial
The large-vial workhorse. Add 3mL of BAC water for 10mg/mL and the full titration is in reach: 2mg = 20 units, 4mg = 40, 8mg = 80, and 12mg = 120 units (the 12mg step needs a 1.5mL syringe or a split draw). A single 30mg vial holds enough peptide for several weeks of dosing, so this size suits anyone past the early titration who wants fewer reconstitutions.
60mg Vial
The bulk-supply size, commonly available from research-peptide suppliers. With 6mL of BAC water it gives 10mg/mL, matching the 30mg setup numbers exactly: 2mg = 20 units, 4mg = 40, 8mg = 80, 12mg = 120 units. More total peptide means fewer vials to reconstitute over a long protocol. A reconstituted 60mg vial also sits in the fridge longer, so label it with the mix date and watch the stability window below.
Storage After Reconstitution
Once mixed, store reconstituted retatrutide like this:
- Refrigerate immediately at 36-46°F (2-8°C).
- Generally considered stable for 28 to 60 days depending on preparation; the conservative practical recommendation is 28 days.
- Label the vial with the reconstitution date.
- Never freeze a reconstituted peptide.
- Discard if the solution turns cloudy, develops particles, or changes color.
That covers the essentials for the chart. For the full storage protocol and handling detail, see the retatrutide storage guide.
Using the GLP3Planner Reconstitution Calculator
The chart above covers the most common setups. For any custom vial size or water volume, the free retatrutide reconstitution calculator computes the exact syringe units for your own concentration. Enter your vial size, your BAC water volume, and your target dose. To model blood levels and steady state across a full titration instead, use the retatrutide half-life calculator. For sterile mixing technique, pair it with the step-by-step reconstitution guide, and for the conversion logic behind it, the BAC water guide for retatrutide.
Video Walkthrough
To see the reconstitution and the unit math demonstrated alongside the chart, this retatrutide-specific walkthrough covers the full mixing process. Use the video for technique and this chart for the numbers, and follow the linked step-by-step reconstitution guide for the exact procedure.
Frequently Asked Questions
How many mL of BAC water for a 10mg retatrutide vial?
The standard is 2mL of bacteriostatic water, producing 5mg/mL where 1mg of retatrutide equals 20 units on a U-100 syringe. A 1mL dilution produces 10mg/mL and is used by some for higher doses to keep the draw small. Both are valid; choose based on your dose range.
What is the best concentration for reconstituting retatrutide?
For doses of 2mg to 4mg, 5mg/mL (2mL per 10mg vial) gives manageable draw volumes. For doses near 8mg to 12mg, 10mg/mL keeps the syringe draw lower. Neither is clinically mandated. Retatrutide is investigational; work with a prescribing provider.
How do I calculate the units for my retatrutide dose?
Use units = (desired dose in mg / concentration in mg per mL) times 100. Concentration is your vial size divided by the BAC water volume added. For a 10mg vial and 2mL of water, concentration is 5mg/mL. A 2mg dose is then (2 / 5) times 100 = 40 units on a U-100 syringe.
What does n/a mean in a retatrutide reconstitution chart?
A cell marked n/a means the dose in that column exceeds the total amount of retatrutide in the vial, so it is physically impossible to draw. For example, a 12mg dose from a 5mg vial is n/a. A dose that fits the vial but needs more than 100 units is not n/a; it just needs a larger syringe or a split draw.
Is 2mg of retatrutide a lot?
2mg is the standard starting dose in the Phase 2 retatrutide trial protocol. The titration runs 2mg, then 4mg, then 8mg, then 12mg in four-week intervals. At 2mg most users are in the early adjustment phase. Retatrutide is investigational; dosing decisions belong with a healthcare provider.
How much BAC water for a 30mg retatrutide vial?
The standard for a 30mg vial is 3mL of bacteriostatic water, giving 10mg/mL. At this concentration 2mg = 20 units, 4mg = 40, 8mg = 80, and 12mg = 120 units (the 12mg draw needs a 1.5mL syringe or a split). Use the chart above for every dose at a glance.
What is the formula for peptide reconstitution?
The formula is units = (desired dose in mg / concentration in mg per mL) times 100. Concentration is vial mg divided by BAC water mL added. On a U-100 insulin syringe, 100 units equals exactly 1mL. This applies to retatrutide and all other lyophilized peptides reconstituted with bacteriostatic water.
How long is reconstituted retatrutide stable?
Stored in a refrigerator at 36-46°F (2-8°C), reconstituted retatrutide is generally considered stable for 28 to 60 days depending on preparation. The conservative practical recommendation is 28 days. Label the vial with the reconstitution date. See the retatrutide storage guide for full details.
Can I use a standard 1mL insulin syringe for all retatrutide doses?
Not always. A U-100 insulin syringe holds a maximum of 100 units. At 5mg/mL, doses above 5mg exceed the syringe. At 10mg/mL, doses above 10mg exceed it. For draws over 100 units, use a 1.5mL or 3mL syringe, or split the dose into two equal injections.
What vial sizes does retatrutide come in?
Research-peptide retatrutide is commonly sold in 5mg, 10mg, 15mg, 20mg, 30mg, and 60mg vials. The 10mg and 30mg sizes are referenced most often. Retatrutide is investigational and not FDA-approved. The FDA states it cannot be used in compounding under federal law, and the FDA has warned companies that illegally sold retatrutide falsely labeled "for research purposes". In the US, lawful access is limited to a clinical trial or Lilly's narrow expanded access program (NCT07629401).
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References
- Jastreboff AM, Kaplan LM, Frías JP, et al. Triple-Hormone-Receptor Agonist Retatrutide for Obesity, A Phase 2 Trial. N Engl J Med. 2023;389(6):514-526. doi:10.1056/NEJMoa2301972.
- Coskun T, Urva S, Roell WC, et al. LY3437943, a novel triple glucagon, GIP, and GLP-1 receptor agonist for glycemic control and weight loss: From discovery to clinical proof of concept. Cell Metab. 2022;34(9):1234-1247.e9. doi:10.1016/j.cmet.2022.07.013. PMID: 35985340.
- U.S. National Library of Medicine. ClinicalTrials.gov: NCT05929079 (TRIUMPH-2, Phase 3 retatrutide). Accessed 2026.
- U.S. Food and Drug Administration. FDA's Concerns with Unapproved GLP-1 Drugs Used for Weight Loss. Content current as of 10/01/2026.
Medical Disclaimer: This reconstitution chart is for informational purposes only and does not replace professional medical advice. Retatrutide is an investigational compound that is not FDA approved, and the FDA states it cannot be used in compounding under federal law. In the US, lawful access is limited to a clinical trial or Lilly's narrow expanded access program (NCT07629401). Always confirm your dose, concentration, and syringe with a qualified healthcare professional before any use.
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