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Tirzepatide reconstitution calculator.
Reconstituting a lyophilized tirzepatide vial? Enter the mg in the vial, the bacteriostatic water you add, and your target dose. You get the exact concentration, the volume to draw in mL, and the units on a U-100 syringe. No rounding, no account, and the full math is shown.
Units shown for a U-100 insulin syringe (1 mL = 100 units). No rounding · the full math is above.
How the math works
Three steps, no hand-waving.
Reconstitution is simple arithmetic. The only thing that matters is that it is exact, and that you can see every step.
Vial mg ÷ BAC water mL = mg/mL. A 10 mg vial in 2 mL of water is 5.0000 mg/mL.
Target dose ÷ concentration = mL to draw. 2.5 mg ÷ 5.0000 mg/mL = 0.5000 mL.
Draw mL × 100 = units on a U-100 insulin syringe. 0.5000 mL = 50 units.
Background
What tirzepatide reconstitution is
Tirzepatide is a dual GIP/GLP-1 receptor agonist. When supplied as a lyophilized powder, it must be reconstituted with bacteriostatic water before a dose can be drawn. The math is the same as any peptide: concentration equals the mg in the vial divided by the mL of water added. This calculator runs that arithmetic exactly and shows your draw volume and syringe units.
- Reconstitution built into the dose logger, not a separate tool
- 28-day BAC water expiry countdown per vial
- Doses remaining and refill warnings, all derived
- Local-first · no account, data stays on your device
FAQ
Tirzepatide reconstitution questions, answered.
How do you calculate tirzepatide reconstitution?
Divide the mg of tirzepatide in the vial by the mL of bacteriostatic water you add for the concentration in mg/mL. Then divide your target dose (in mg) by that concentration to get the draw volume in mL. Multiply the volume by 100 for units on a U-100 insulin syringe.
How much bacteriostatic water do I add to tirzepatide?
There is no single correct amount. More water lowers the concentration and gives a larger, easier-to-measure draw; less water gives a higher concentration and a smaller draw. Enter the amount you actually plan to add and the calculator shows the result. Follow your provider's or pharmacy's instructions.
How many units is a tirzepatide dose?
It depends on your concentration. Enter your vial mg, BAC water mL, and target dose above and the calculator returns the exact units on a U-100 syringe, updating live.
Why does getting the exact tirzepatide dose matter?
At these concentrations a small volume error becomes a large dose error. The FDA has documented people drawing five to twenty times the intended amount from compounded vials, with serious adverse events. Showing the draw volume and units to four decimal places is how this tool cuts the guesswork. Confirm your numbers with your provider or pharmacist.
How should reconstituted tirzepatide be stored?
Follow the storage guidance for your specific product. Reconstituted vials are generally refrigerated and used within a limited window. Regimio tracks a per-vial expiry countdown so you do not have to guess how many days are left.
Is compounded tirzepatide still legal?
Compounded tirzepatide was available mainly because the approved drug was in shortage. The FDA declared that shortage resolved in December 2024, so routine compounding is no longer generally permitted, with only a narrow patient-specific exception. This is a regulatory summary, not legal advice.
Is this medical advice?
No. This calculator performs arithmetic on the values you enter. It does not recommend a dose, schedule, or source. Confirm all medication instructions with your clinician or pharmacist.
- 1Tirzepatide compound summary. PubChem, US National Library of Medicine
- 2FDA's Concerns with Unapproved GLP-1 Drugs Used for Weight Loss. U.S. Food & Drug Administration
This tool performs reconstitution arithmetic only. It is not medical advice and does not recommend any compound, dose, schedule, or source. Always follow guidance from a qualified provider. See our medical disclaimer.