Short answer: The Zepbound vial Instructions for Use describe a new syringe and needle each week: pull air into the syringe to the dose line (0.5 mL for a single-dose vial, 0.6 mL for a multi-dose vial), push the air into the vial, turn it upside down, draw past the line, tap out bubbles and push back to the line. The dose goes under the skin of the stomach or thigh, or the back of the upper arm if someone else gives it.
Zepbound (tirzepatide) comes in pens and in two kinds of vial. A single-dose vial holds one weekly dose in 0.5 mL. A multi-dose vial holds 2.4 mL, which the label describes as 4 weekly doses of 0.6 mL each. Because the volume per dose differs, the same dose in milligrams is a different amount of liquid depending on the vial.
| Dose | Single-dose vial | Multi-dose vial (4 doses) |
|---|---|---|
| 2.5 mg | 2.5 mg/0.5 mL | 0.6 mL per dose, 4.17 mg/mL |
| 5 mg | 5 mg/0.5 mL | 0.6 mL per dose, 8.33 mg/mL |
| 7.5 mg | 7.5 mg/0.5 mL | 0.6 mL per dose, 12.5 mg/mL |
| 10 mg | 10 mg/0.5 mL | 0.6 mL per dose, 16.7 mg/mL |
| 12.5 mg | 12.5 mg/0.5 mL | 0.6 mL per dose, 20.8 mg/mL |
| 15 mg | 15 mg/0.5 mL | 0.6 mL per dose, 25 mg/mL |
Syringes and needles are not included. The Instructions for Use give a 1 mL syringe and needle as an example and say to use the ones the healthcare provider recommends. The label asks that anyone switching between presentations, such as from pens to vials, be trained on the new one first.
Before starting, the label says to check the vial label for the right medicine, dose and expiry date, and to check that the liquid is not frozen, not cloudy, colorless to slightly yellow, and free of particles. It says to use a new syringe and needle for every injection and never to share them.
The label lists the stomach area and thighs for self-injection, and the back of the upper arm when someone else injects. It says to change (rotate) the spot within the chosen area each week to lower the risk of pits, thickened skin or lumps, and not to inject into skin that is tender, bruised, scaly, hard, scarred or lumpy. It also says not to mix Zepbound with any other medicine or use the same spot as another injected medicine.
After inserting the needle and pushing the plunger, the label says to keep the needle in the skin for at least 5 seconds so the whole dose goes in. If there is blood, press with gauze without rubbing. The needle is not recapped; the syringe goes straight into a sharps container. FDA describes what counts as a safe household container and how to follow local disposal rules.
| Single-dose vial | Multi-dose vial | |
|---|---|---|
| Unopened | Refrigerator, 36 to 46°F | Refrigerator, 36 to 46°F, until the expiry date |
| Unopened, room temperature (up to 86°F) | Up to 21 days in total | Up to 30 days |
| After first use | Throw away after the one dose, even with liquid left | Fridge or room temperature; throw away after 30 days at room temperature, 30 days after first use, or 4 weekly doses, whichever comes first |
Both vial types are kept in the carton to protect them from light and are not used if they have been frozen. Dose Track can keep each vial with its open date and dose count, so it is clear when a multi-dose vial reaches its 30 days or its fourth dose.
Read more on Dose Track: Zepbound overview · Zepbound dosing schedule · How to store Zepbound · Multi-dose vial · Sharps disposal