The quick answer
Both tirzepatide labels say the same thing: inject in the abdomen or thigh, or have another person inject in the back of the upper arm. Both also say to rotate injection sites with each dose. The buttocks are not a listed site.
What each label says
| Medication | Sites | Upper arm | Rotation |
|---|---|---|---|
| Mounjaro® Label | Abdomen or thigh, or back of the upper arm | “Have another person inject … in the back of the upper arm.” | “Rotate injection sites with each dose.” Same area is fine, but choose a different site in that area. |
| Zepbound® Label | Abdomen or thigh, or back of the upper arm | “Another person should inject in the back of the upper arm.” | “Rotate injection sites with each dose.” The Medication Guide: “Do not use the same site for each injection.” |
Pens, KwikPens, and vials
The instructions differ a little by device, so check the leaflet in your box:
- Single-dose pen. Zepbound’s instructions: “You or another person can inject the medicine in your stomach (abdomen) or thigh. Another person should give you the injection in the back of your upper arm.”
- KwikPen. Thigh or stomach, at least 2 inches from the belly button. The upper arm still needs another person.
- Vials. Rotate the injection site within the area you choose to reduce the risk of skin changes (lipodystrophy). Don’t inject where the skin is tender, bruised, scaly, or hard, or into scars or damaged skin. The Zepbound vial instructions add: don’t use the same site you use for other medicines.
Rotating within an area
You don’t have to switch body areas every time. The pen instructions say you may use the same area of your body, but choose a different injection site in that area. MedlinePlus’s general advice for subcutaneous shots is to move at least 1 inch from the last spot.
Why it matters: repeated injections in one spot are linked to lumpy or thickened tissue under the skin, and the vial instructions name that risk directly. More on why rotation matters.
If you also use insulin
The Mounjaro label says it is acceptable to inject Mounjaro and insulin in the same body region, but the injections should not be next to each other. The Zepbound label doesn’t address this, so ask your prescriber.
Keeping a record
The easy part of rotation is the rule. The hard part is remembering which side you used last time. Print the free rotation chart (PDF), or let StackLogR save the site in the same tap as the log. It works for GLP-1 tracking alongside anything else you take.
Using semaglutide instead? See semaglutide injection sites (Ozempic, Wegovy).
FAQ
Where do you inject tirzepatide?
The Mounjaro and Zepbound labels list the abdomen (stomach) and the thigh, plus the back of the upper arm when another person gives the injection.
Can I inject Zepbound or Mounjaro in my arm myself?
The labels say another person should give the injection in the back of the upper arm. On your own, the labeled areas are the stomach and the thigh. Ask your prescriber or pharmacist if you’re unsure.
Can I use the same area every time?
The labels say you can use the same area of your body, but choose a different injection site in that area each time. Their prescribing information says to rotate injection sites with each dose.
How far from the belly button should a tirzepatide injection be?
The Mounjaro and Zepbound KwikPen instructions say at least 2 inches from the belly button. MedlinePlus gives the same distance for subcutaneous injections in general.
Can I inject Mounjaro and insulin in the same area?
The Mounjaro label says it is acceptable to inject Mounjaro and insulin in the same body region, but the injections should not be adjacent to each other.
Does it matter which tirzepatide site I pick?
The labels list the allowed areas and don’t rank them. Pick within those areas with your prescriber, and rotate so you’re not using the same spot each time.