How many units is 2.5 mg of tirzepatide?
2.5 mg of tirzepatide is 25 units on a U-100 syringe from a 10 mg/mL vial, 50 units from a 5 mg/mL vial, and 12.5 units from a 20 mg/mL vial.
Medically reviewed by Dr. Nezar Dahdal, Medical Director · last reviewed September 2026
2.5 mg of tirzepatide in units, by vial strength
| Prescribed dose | 5 mg/mL vial | 10 mg/mL vial | 20 mg/mL vial |
|---|---|---|---|
| 2.5 mg | 50 units (0.5 mL) | 25 units (0.25 mL) | 12.5 units (0.125 mL) |
2.5 mg is the starting dose in the prescribing information: four weeks to let the digestive system adjust. It is not a treatment dose. Your prescriber decides when, and whether, to change it.
Tirzepatide dose calculator
Enter the dose your prescriber gave you and the concentration printed on your vial label. The calculator converts it to units on a U-100 insulin syringe.
Enter your prescribed dose and your vial concentration to see the units.
This converts a dose you have already been prescribed. It does not recommend a dose. Always use the concentration printed on your pharmacy label. If the number here does not match what you were told, stop and call your prescriber before injecting.
Compounded tirzepatide and semaglutide are not FDA-approved. They are prepared by a licensed pharmacy for an individual patient, and their strength varies from pharmacy to pharmacy, which is exactly why the concentration on your own label is the number that matters. Brand pens (Zepbound, Mounjaro, Wegovy, Ozempic) deliver a fixed dose and need no conversion.
Every dose in one chart
The units for every tirzepatide dose step are in the tirzepatide dosage chart, alongside the weekly schedule from the prescribing information.
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Answers before you book
How many units is 2.5 mg of tirzepatide?
2.5 mg of tirzepatide is 25 units on a U-100 syringe from a 10 mg/mL vial, 50 units from a 5 mg/mL vial, and 12.5 units from a 20 mg/mL vial. Always use the concentration printed on your own vial.
How many mL is 2.5 mg of tirzepatide?
0.25 mL from a 10 mg/mL vial, 0.5 mL from 5 mg/mL, and 0.125 mL from 20 mg/mL.
What if my vial is a different strength?
Divide the dose in mg by the vial concentration in mg/mL and multiply by 100, or use the calculator on this page.
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