Quick math example
A 10 mg vial mixed with 2 mL gives 5 mg/mL. A 2.5 mg dose is 0.5 mL, which equals 50 units on a U-100 syringe.
Tirzepatide 30 mg vial reference
U100 units to draw for each common Tirzepatide dose, by vial size, reconstituted with 3 mL of bacteriostatic water. Change the water volume in the calculator above to recompute for your own setup.
| Vial | Concentration | 2.5 mg | 5 mg | 7.5 mg | 10 mg | 12.5 mg |
|---|---|---|---|---|---|---|
| 30 mg | 10 mg/mL | 25 u(0.25 mL) | 50 u(0.5 mL) | 75 u(0.75 mL) | 100 u(1 mL) | 125 u(1.25 mL) |
Educational reference only — not a dose recommendation. Units assume a U100 insulin syringe (100 units = 1 mL on U-100). Always confirm against your own vial, diluent, and clinician or pharmacy instructions.
30 mg tirzepatide vial examples
A 30 mg vial in 3 mL gives 10 mg/mL (10,000 mcg/mL). A 2.5 mg dose is 0.25 mL, which is 25 units on a U-100 syringe.
Because the vial is so concentrated, larger maintenance doses stay easy to draw: 5 mg is 0.5 mL (50 units) and 10 mg is a full 1.0 mL (100 units). Above 10 mg you would exceed a standard 1 mL syringe, so add more water if you dose that high.
- 30 mg / 3 mL = 10 mg/mL → 2.5 mg = 0.25 mL = 25 units
- 30 mg / 3 mL = 10 mg/mL → 5 mg = 0.5 mL = 50 units
- 30 mg / 6 mL = 5 mg/mL → 2.5 mg = 0.5 mL = 50 units (easier early-titration draws)
When a 30 mg tirzepatide vial makes sense
The 30 mg vial suits established maintenance dosing where you are running 10–15 mg per week and want to reconstitute far less often. At 2.5 mg per week it holds about twelve doses; at 5 mg per week, about six. That is several weeks of protocol per vial, which reduces handling but means the beyond-use clock matters more.
It is a poor fit for the earliest titration weeks: a 2.5 mg starting dose from a 30 mg vial is a very small draw unless you use more water, and you would be carrying a large amount of peptide in a single open vial for a long time.
- Best for 10–15 mg/week maintenance dosing
- ~12 doses at 2.5 mg; ~6 at 5 mg before dead-space loss
- Confirm the beyond-use date — one vial spans several weeks
How the tirzepatide calculation works
Tirzepatide doses are often discussed in milligrams, while many vials and syringes require you to think in mg, mcg, mL, and units at the same time.
The calculator normalizes everything into concentration first, then returns a draw volume and matching syringe-unit result.
- 10 mg equals 10,000 mcg
- 10,000 mcg / 2 mL = 5,000 mcg per mL
- 2,500 mcg / 5,000 mcg per mL = 0.5 mL
Tirzepatide 10 mg vial with 2 mL example
A 10 mg tirzepatide vial mixed with 2 mL gives 5 mg/mL, or 5,000 mcg/mL.
A 2.5 mg target dose is 2,500 mcg. At 5 mg/mL, that is 0.5 mL, which equals 50 units on a U-100 syringe.
- 10 mg / 2 mL = 5 mg/mL
- 2.5 mg = 2,500 mcg
- 2,500 mcg / 5,000 mcg per mL = 0.5 mL = 50 U-100 units
Tirzepatide 15 mg vial with 3 mL example
A 15 mg tirzepatide vial mixed with 3 mL also gives 5 mg/mL, or 5,000 mcg/mL.
Because the concentration is the same as the 10 mg with 2 mL example, a 2.5 mg dose is still 0.5 mL, or 50 U-100 units.
- 15 mg / 3 mL = 5 mg/mL
- 2.5 mg / 5 mg per mL = 0.5 mL
- 0.5 mL x 100 = 50 U-100 units
How much BAC water for tirzepatide?
Bacteriostatic water volume sets your concentration, so it directly changes the syringe units you draw. There is no single correct amount — choose a volume that puts your target dose at an easy-to-read number of units on a U-100 syringe.
For a 10 mg vial: 1 mL gives 10 mg/mL (a 2.5 mg dose = 0.25 mL = 25 units), 2 mL gives 5 mg/mL (2.5 mg = 0.5 mL = 50 units), and 3 mL gives about 3.33 mg/mL (2.5 mg = 0.75 mL = 75 units).
- More BAC water = lower concentration = more units for the same dose
- 10 mg / 1 mL = 10 mg/mL; 10 mg / 2 mL = 5 mg/mL; 10 mg / 3 mL = 3.33 mg/mL
- Aim for a draw that lands on clear unit markings to reduce dosing error
When to re-check the math
Recalculate when you change vial size, BAC water volume, dose, syringe type, or syringe capacity. Saving the setup in PepSync helps avoid re-entering the same details each week.