How Many Units Is 12.5 mg of Tirzepatide? U-100 Chart
[GLP-1 units · Tirzepatide · 12.5 mg]

How many units is 12.5 mg of tirzepatide?

Units at every vial strength · Label schedule · Reviewed

Short answer: 12.5 mg of tirzepatide is 250 units on a U-100 syringe at 5 mg/mL, 156.25 units at 8 mg/mL, 125 units at 10 mg/mL, 83.33 units at 15 mg/mL and 62.5 units at 20 mg/mL. In volume that is 2.5 mL at 5 mg/mL, 1.5625 mL at 8 mg/mL, 1.25 mL at 10 mg/mL, 0.8333 mL at 15 mg/mL and 0.625 mL at 20 mg/mL. Compounded products are not FDA approved; check the strength on your vial label, because the units are only right for that strength.

Compounded vs FDA-approved. Compounded tirzepatide is not FDA approved, and FDA does not review compounded drugs for safety, effectiveness or quality before they are sold (FDA). Mounjaro and Zepbound single-dose pens each hold one fixed dose, and the KwikPen is set to its labeled dose, so the dose is chosen in mg and there are no syringe units to work out. The labeled single-dose vials are one dose each, and the labeled multi-dose vial gives four doses of 0.6 mL; follow the instructions for use that come with them, not a compounded units chart.

How many units is 12.5 mg at each vial strength?

Each row converts 12.5 mg at one compounded tirzepatide strength for a U-100 insulin syringe (1 mL = 100 units). Not personalized advice; confirm your dose, in mg and in units, with your prescriber or the dispensing pharmacy.

12.5 mg of tirzepatide, U-100 insulin syringe. Click a strength for every dose at that strength.
Vial strengthVolumeU-100 unitsSmallest syringe that holds it
5 mg/mL2.5 mL250 unitsMore than one 1 mL syringe
8 mg/mL1.5625 mL156.25 units (between marks)More than one 1 mL syringe
10 mg/mL1.25 mL125 unitsMore than one 1 mL syringe
15 mg/mL0.8333 mL83.33 units (between marks)1 mL (100 units)
20 mg/mL0.625 mL62.5 units1 mL (100 units)

"Between marks" means the volume does not land on a printed line, even on a 0.3 mL syringe with half-unit markings. See U-40 vs U-100 syringes and how to read the marks.

How do you check the math?

Divide the dose by the strength to get mL, then multiply by 100 for U-100 units. To check, run it backwards: units ÷ 100 × mg/mL should give back 12.5 mg.

  • 5 mg/mL. 12.5 mg ÷ 5 mg/mL = 2.5 mL × 100 = 250 units; check: 250 ÷ 100 × 5 = 12.5 mg
  • 8 mg/mL. 12.5 mg ÷ 8 mg/mL = 1.5625 mL × 100 = 156.25 units; check: 156.25 ÷ 100 × 8 = 12.5 mg
  • 10 mg/mL. 12.5 mg ÷ 10 mg/mL = 1.25 mL × 100 = 125 units; check: 125 ÷ 100 × 10 = 12.5 mg
  • 15 mg/mL. 12.5 mg ÷ 15 mg/mL = 0.8333 mL × 100 = 83.33 units; check: 83.33 ÷ 100 × 15 = about 12.5 mg
  • 20 mg/mL. 12.5 mg ÷ 20 mg/mL = 0.625 mL × 100 = 62.5 units; check: 62.5 ÷ 100 × 20 = 12.5 mg

If the units on your instructions do not match this math for the strength on your vial, ask the prescriber or pharmacy before injecting.

Where is 12.5 mg in the label schedule?

In the Mounjaro label, 12.5 mg is dose step 5 of 6. The schedule has no fixed weeks for 12.5 mg; the label reaches it with this step: Further steps: If more glycemic control is needed, increase by 2.5 mg after at least 4 weeks on the current dose. (Mounjaro label)

In the Zepbound label, 12.5 mg is dose step 5 of 6. The schedule has no fixed weeks for 12.5 mg; the label reaches it with this step: Further steps: Increase by 2.5 mg after at least 4 weeks on the current dose. (Zepbound label)

Compounded tirzepatide has no FDA label of its own. For reference, these are the schedules in the FDA labels that name 12.5 mg, with its rows highlighted.

Zepbound (FDA label, section 2)

Label schedule, quoted from the prescribing information. Your prescriber sets your own schedule.
WhenLabel dose
Weeks 1 to 42.5 mg once weekly (for starting treatment only)
Week 55 mg once weekly
Further stepsIncrease by 2.5 mg after at least 4 weeks on the current dose
Maintenance5 mg, 10 mg or 15 mg once weekly for weight reduction; 10 mg or 15 mg for obstructive sleep apnea
Maximum15 mg once weekly

The label states that 2.5 mg is for starting treatment and is not an approved maintenance dose.

Mounjaro (FDA label, section 2)

Label schedule, quoted from the prescribing information. Your prescriber sets your own schedule.
WhenLabel dose
Start2.5 mg once weekly
Further stepsIf more glycemic control is needed, increase by 2.5 mg after at least 4 weeks on the current dose
Maximum15 mg once weekly in adults

For pediatric patients 10 years and older the Mounjaro label sets a lower maximum of 10 mg once weekly.

Full schedules: Mounjaro dosing schedule · Zepbound dosing schedule

Other tirzepatide doses

Previous step: 10 mg · Next step: 15 mg

2.5 mg · 5 mg · 7.5 mg · 10 mg · 15 mg · All tirzepatide doses and strengths in one grid

Mixing a powder vial instead? The tirzepatide reconstitution guide and the free reconstitution calculator handle vials you add water to.

Frequently asked questions

Is 12.5 mg of tirzepatide the same as 250 units?+
Only at 5 mg/mL. Units measure volume, not drug, so the same 12.5 mg is 156.25 units at 8 mg/mL, 125 units at 10 mg/mL, 83.33 units at 15 mg/mL and 62.5 units at 20 mg/mL on a U-100 insulin syringe. Check the strength printed on your vial label before you count units. Not personalized advice; confirm your dose, in mg and in units, with your prescriber or the dispensing pharmacy.
How many mL is 12.5 mg of tirzepatide?+
12.5 mg ÷ the vial strength = mL: 2.5 mL at 5 mg/mL, 1.5625 mL at 8 mg/mL, 1.25 mL at 10 mg/mL, 0.8333 mL at 15 mg/mL, 0.625 mL at 20 mg/mL. On a U-100 syringe, every 0.01 mL is 1 unit.
Can 12.5 mg of tirzepatide be measured on an insulin syringe?+
At 5 mg/mL it is 250 units, which needs more than one 1 mL syringe; at 8 mg/mL it is 156.25 units, which needs more than one 1 mL syringe; at 10 mg/mL it is 125 units, which needs more than one 1 mL syringe; at 15 mg/mL it is 83.33 units, which fits a 1 mL (100 units) syringe; at 20 mg/mL it is 62.5 units, which fits a 1 mL (100 units) syringe. At 8 mg/mL and 15 mg/mL the volume does not land on a printed mark, even on a half-unit scale, so ask the prescriber or pharmacy how they want it measured.
How long does the label keep tirzepatide at 12.5 mg?+
In the Mounjaro label, 12.5 mg is dose step 5 of 6. The schedule has no fixed weeks for 12.5 mg; the label reaches it with this step: Further steps: If more glycemic control is needed, increase by 2.5 mg after at least 4 weeks on the current dose. In the Zepbound label, 12.5 mg is dose step 5 of 6. The schedule has no fixed weeks for 12.5 mg; the label reaches it with this step: Further steps: Increase by 2.5 mg after at least 4 weeks on the current dose. These are the FDA label schedules for Mounjaro and Zepbound; compounded tirzepatide has no FDA label, and your prescriber sets your own schedule.