Zepbound Dose Chart: Doses, Pens, and Vial Units
This is a dose reference, not medical advice. Follow your prescription and the instructions on your pen or vial.
Zepbound Dose Chart
| Dose | When it's typically used | Vial draw (U-100 syringe) |
|---|---|---|
| 2.5 mg | Weeks 1-4 (starter) | 0.5 mL = 50 units |
| 5 mg | Weeks 5-8 | 0.5 mL = 50 units |
| 7.5 mg | Weeks 9-12 | 0.5 mL = 50 units |
| 10 mg | Weeks 13-16 | 0.5 mL = 50 units |
| 12.5 mg | Weeks 17-20 | 0.5 mL = 50 units |
| 15 mg | Week 21 onward | 0.5 mL = 50 units |
The 2.5 mg dose is a starter to ease side effects, not a treatment dose. Most people step up about every four weeks, though holding at a dose that's working is common and fine.
The part that confuses people: 50 units is not a milligram amount
Every Zepbound single-dose vial holds 0.5 mL, and 0.5 mL is 50 units on a standard U-100 insulin syringe. That's true for the 2.5 mg vial and the 15 mg vial alike.
So the units don't tell you the dose. The vial does.
On a 2.5 mg vial, drawing 50 units gives you 2.5 mg. On a 10 mg vial, that same 50 units gives you 10 mg. The concentration is different in each vial, and the strength printed on the label is your real dose. Draw the full vial and you've drawn your full dose.
Pen or vial: what's the difference
The Zepbound pen is a single-use auto-injector. You press it to your skin and it delivers the full preset dose. No dial, no clicks, nothing to measure.
The vial is the same medicine at the same weekly strengths, but you draw it into an insulin syringe and inject it yourself. Lilly offers vials through self-pay at a lower price than the pens, which is why a lot of people choose them.
Same drug, same doses. The vial just asks you to do the drawing.
Zepbound and Mounjaro are the same molecule
Zepbound and Mounjaro are both tirzepatide. Zepbound is the version approved for weight loss, Mounjaro for type 2 diabetes. The doses and the titration ladder are the same.
If your prescription switched brands but kept the dose, your schedule doesn't change. The Mounjaro dose chart covers the same six strengths from the diabetes side.
Compounded tirzepatide is a different draw
Compounded tirzepatide isn't a fixed 50-unit vial. It's mixed to a concentration your pharmacy chose, so the units for your dose depend on that specific vial.
Same molecule as brand Zepbound, different product. Brand vials are FDA-approved and quality-controlled, so the fill is standardized at 0.5 mL. Compounded vials are not FDA-approved, so the concentration and the units change source to source. Our tirzepatide reconstitution calculator works out the units for your exact concentration, and the compounded semaglutide and tirzepatide guide has the full picture.
Track your dose, vial, and weight together
Which vial you're on, when you last stepped up, how the scale and your side effects moved with each change: that's the stuff worth having in one place instead of scattered across your memory.
Regimen logs your dose, your form (pen or vial), and how you're responding on one timeline, and reminds you when your weekly shot is due. Track your Zepbound doses in Regimen.
Frequently Asked Questions
How many units is a Zepbound vial?
Every single-dose vial is 0.5 mL, which is 50 units on a U-100 insulin syringe, at every strength. You draw the full vial. The milligrams come from which vial you have, not the unit count.
Is 50 units the same as 2.5 mg of Zepbound?
Only on a 2.5 mg vial. On a 10 mg vial, 50 units is 10 mg. Each vial is a different concentration, so read the strength on the label for your actual dose.
What are all the Zepbound doses?
Six weekly strengths: 2.5, 5, 7.5, 10, 12.5, and 15 mg. The 2.5 mg dose is a starter, and 5 mg and up are the treatment doses.
Does the Zepbound pen have clicks?
No. The pen is a fixed-dose auto-injector that delivers the full dose on its own. There's no dial to turn or clicks to count, unlike Ozempic.
What happens if I miss a Zepbound dose?
If four days (96 hours) or less have passed since your scheduled day, take it when you remember. If it's been more than four days, skip it and take your next dose on the regular day. Don't take two doses within three days.
What app tracks Zepbound doses?
Regimen tracks your dose, pen or vial, and side effects on one timeline and reminds you when your shot is due.
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