Mounjaro (tirzepatide) is an effective weight loss medication that you inject once weekly. If you've just received your first prescription, you might be wondering how to use your Mounjaro pen correctly. This guide will walk you through every step of the injection process safely and confidently.
Before you begin, gather these items:
Your Mounjaro pen
An alcohol wipe
A sharps disposal container
Cotton wool or gauze (optional)
Always perform these safety checks before using your Mounjaro pen:
Check the label: Confirm it says Mounjaro, shows the correct dose, and hasn't expired.
Inspect the liquid: Look through the window on your pen. The liquid should be clear and colourless or slightly yellow. Don't use the pen if the liquid is cloudy, discoloured, or contains particles.
Bring to room temperature: Take your pen out of the fridge 30 minutes before injecting. Injecting at room temperature is more comfortable than injecting cold medication.
Never use a frozen pen: If your Mounjaro pen has been frozen, you must dispose of it safely and use a new one.
Mounjaro can be injected into two areas of your body:
Your stomach (abdomen), avoiding a 5cm area around your belly button
The front of your thighs
It's important to rotate where you inject each week. This prevents skin irritation and helps the medication work effectively.
Choose a spot at least 5cm away from where you injected last time. You might find it helpful to keep a simple record of your injection sites.
Wash your hands thoroughly with soap and water
Clean your chosen injection site with an alcohol wipe
Let the area dry completely (about 30 seconds)
Turn the lock ring on your pen until you feel it click – this unlocks the pen
Pull the base cap straight off
You'll see a clear base where the needle is hidden inside
Don't touch the clear base
Place the clear base flat against your skin at your chosen injection site
Hold the pen at a 90-degree angle (straight up and down)
You'll see a purple indicator appear in the window when the pen touches your skin – this means you're ready to inject
Press and hold the purple injection button firmly
You'll hear a first click. This is the injection starting
Keep holding the button down
You'll hear a second click and feel the pen vibrate. This means the injection is complete
You'll now see a grey plunger visible in the window, confirming your full dose has been delivered
Remove the pen straight out from your skin
You might see a small amount of liquid or blood at the injection site. This is normal
If needed, gently press with cotton wool, but don't rub the area
Proper disposal is crucial for safety:
Place the used pen immediately into your sharps disposal container
Never throw it in your household bin or recycling
Each Mounjaro pen contains only one dose and cannot be reused
If you need a sharps container, your pharmacy can provide one, or contact your Everwell medical team.
Unused pens: Store in the fridge between 2°C and 8°C. Keep them in the original packaging to protect from light.
Never freeze: If a pen has been frozen, it must be thrown away.
After use: Once used, pens should be disposed of immediately. If needed, you can keep a used pen at room temperature for up to 21 days, but immediate disposal is best practice.
How often do I inject Mounjaro? Once weekly, on the same day each week.
Does the Mounjaro injection hurt? Most people find the injection relatively painless. Using room temperature medication and rotating injection sites helps minimise discomfort.
What if I miss a dose? Contact your Everwell medical team for guidance on missed doses.
Can I inject through clothing? No, always inject into clean, bare skin.
If you have any questions or concerns about injecting Mounjaro, contact your Everwell medical team at clinic@joineverwell.ie. We're here to support you throughout your weight loss journey.
Your Mounjaro prescription is just one part of your comprehensive Everwell programme. Combined with lifestyle coaching and ongoing medical support, it gives you the best chance of achieving sustainable weight loss.
This guide is for informational purposes only. Always follow the specific instructions provided by your doctor and the patient information leaflet included with your medication.
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