At a glance
| Mark on U-100, 1 mL | Volume | at 4.17 mg/mL Zepbound 10 mg multi-dose vial | at 5 mg/mL Zepbound 2.5 mg single-dose vial | at 8.33 mg/mL Zepbound 20 mg multi-dose vial | at 10 mg/mL Zepbound 5 mg single-dose vial | at 12.5 mg/mL Zepbound 30 mg multi-dose vial | at 16.7 mg/mL Zepbound 40 mg multi-dose vial | at 20 mg/mL Zepbound 10 mg single-dose vial | at 25 mg/mL Zepbound 12.5 mg single-dose vial and 60 mg multi-dose vial |
|---|---|---|---|---|---|---|---|---|---|
| 10 units | 0.1 mL | 0.417 mg | 0.5 mg | 0.833 mg | 1 mg | 1.25 mg | 1.67 mg | 2 mg | 2.5 mg |
| 20 units | 0.2 mL | 0.834 mg | 1 mg | 1.67 mg | 2 mg | 2.5 mg | 3.34 mg | 4 mg | 5 mg |
| 25 units | 0.25 mL | 1.04 mg | 1.25 mg | 2.08 mg | 2.5 mg | 3.13 mg | 4.17 mg | 5 mg | 6.25 mg |
| 30 units | 0.3 mL | 1.25 mg | 1.5 mg | 2.5 mg | 3 mg | 3.75 mg | 5.01 mg | 6 mg | 7.5 mg |
| 40 units | 0.4 mL | 1.67 mg | 2 mg | 3.33 mg | 4 mg | 5 mg | 6.68 mg | 8 mg | 10 mg |
| 50 units | 0.5 mL | 2.08 mg | 2.5 mg | 4.17 mg | 5 mg | 6.25 mg | 8.35 mg | 10 mg | 12.5 mg |
| 60 units | 0.6 mL | 2.5 mg | 3 mg | 5 mg | 6 mg | 7.5 mg | 10.02 mg | 12 mg | 15 mg |
Arithmetic at the concentrations shown. The concentration on your own label is the one that counts; enter it in the calculator.
Why the milligrams depend on the vial
30 units is 0.3 mL, which is also the full capacity of the smallest insulin syringe. That coincidence causes a specific confusion: someone handed a 0.3 mL syringe assumes a full syringe is their dose. It is not, unless the arithmetic says so. 0.3 mL is 1.25 mg from a Zepbound 10 mg multi-dose vial, 1.5 mg at 5 mg/mL, 3 mg at 10 mg/mL, 7.5 mg at 25 mg/mL. The labelled Zepbound draws are 0.5 mL and 0.6 mL, and neither fits a 0.3 mL syringe at all, which is why that syringe is the wrong size for Zepbound vials. For a compounded vial, the pharmacy's concentration decides what 30 units holds, and a 0.3 mL syringe may be exactly right.
The mistake to watch for. A 0.3 mL syringe filled to its top mark is 30 units on any concentration. Whether that is your dose depends on the label, not on the syringe being full.