How many 1mg doses are in a 20mg Tirzepatide vial?
Answer
A 20 mg Tirzepatide vial gives 20 full 1 mg doses. On a once-weekly schedule that is 20 weeks, or about 4.6 months. Reconstitution volume changes the units you draw, not the number of doses.
This page also answers
- How long does a 20mg tirz vial last at 1mg?
- 20mg tirz: how many weeks at 1mg?
- Doses per vial: 20mg at 1mg
How long a 20 mg vial lasts at 1 mg per injection
| Schedule | Injections/week | Weeks per vial | Months |
|---|---|---|---|
| Once weekly | 1 | 20 | 4.6 |
| Twice weekly (split) | 2 | 10 | 2.3 |
| Three times weekly | 3 | 6.7 | 1.5 |
| Every other day | 3.5 | 5.7 | 1.3 |
Split schedules use the same weekly total, so the vial lasts the same number of weeks. You just inject smaller amounts more often.
Common questions
- Does how much water I use change the number of doses?
- No. Doses per vial is total milligrams divided by dose milligrams: 20 ÷ 1 = 20. Bacteriostatic water changes the units you draw, not how many doses are in there.
- How many months does that work out to?
- On a once-weekly schedule, 20 doses is 20 weeks, or about 4.6 months. Splitting the same weekly total across two or three injections doesn't change that; the vial still lasts 20 weeks. Titrating up does: at a higher dose per injection you get fewer doses out of the same 20 mg.
- What if I split the dose twice weekly?
- The vial lasts the same number of weeks. Splitting 1 mg into two half-doses a week keeps the weekly total identical. It only lowers the peak concentration between injections.
- How long is it good for after mixing?
- Refrigerate reconstituted peptide at 36–46°F (2–8°C). Most references give 28–60 days once mixed, depending on the preservative in the bacteriostatic water. Do not freeze it, and inspect for cloudiness or particles before every draw.
Run your own numbers
These figures assume the vial and water volumes named above. Change either one and the units change with it.