Overview
This guide explains how to prepare, prime, and safely inject your MedExpress Mounjaro® pen, and what to do afterwards — use it each time you administer your weekly Mounjaro® injection.
Use this article when you want to:
Prepare and prime your Mounjaro® pen correctly
Check the pen is working before you inject
Choose and rotate a safe injection site
Administer your weekly Mounjaro® dose and dispose of the needle safely.
Video Guide
Step 1: How Do I Prepare My Mounjaro® Pen?
Remove your MedExpress Mounjaro® pen from the refrigerator and place it on a clean surface with:
Alcohol swab
Disposable needle
Sharps bin
Wash your hands thoroughly with soap and water.
Remove the pen cap and inspect the liquid inside the Mounjaro® pen. The liquid should be clear to slightly yellow. Do not use the pen if the liquid is cloudy, discoloured, or the pen is damaged.
Wipe the red inner seal with an alcohol swab.
Check the needle packaging for damage.
Peel off the paper tab, push the needle onto the pen, and twist to secure.
Keep the outer needle cap for safe disposal later.
Step 2: How Do I Prime My Mounjaro® Pen?
Turn the dose knob until you hear 2 clicks.
Confirm the extended line is visible in the dose window.
Step 3: How Do I Clear Air Bubbles From My Mounjaro® Pen?
Hold the Mounjaro® pen with the needle pointing upward.
Gently tap the cartridge holder so air bubbles rise to the top.
Step 4: How Do I Release a Test Droplet?
Hold the Mounjaro® pen upright.
Press the dose knob fully in and hold for 5 seconds.
Confirm the "0" icon appears in the dose window and a droplet forms at the needle tip.
Do not inject during this step.
If no droplet appears:
Prime the Mounjaro® pen again and repeat up to two more times.
If still unsuccessful, attach a new needle and try once more.
If a droplet still does not appear, the pen may be unusable.
Step 5: Where Can I Inject Mounjaro®?
Mounjaro® can be injected into:
The stomach, at least 5 cm away from the belly button
The front of the thigh
The back of the upper arm (may require assistance)
Rotate your injection site each week to reduce skin irritation.
Step 6: How Do I Set My Mounjaro® Dose?
Turn the dose knob until it stops and the "1" icon appears in the dose window.
Step 7: How Do I Administer My Mounjaro® Injection?
Hold the Mounjaro® pen at a 90-degree angle to the skin.
Press and hold the injection button fully until the "0" icon appears in the dose window.
Keep holding for 5 additional seconds to make sure the full dose is delivered.
Remove the needle from the skin.
If a small amount of blood appears, press gently on the injection site with a clean tissue. Do not rub.
What Should I Do After My Mounjaro® Injection?
Carefully replace the outer needle shield.
Unscrew the needle and place it in a sharps container. Do not store your MedExpress Mounjaro® pen with a needle attached.
Replace the pen cap. Do not store the Mounjaro® pen without the cap attached.