How to Use Mounjaro: Complete Injection Guide
Step-by-step instructions for safe and effective Mounjaro (tirzepatide) administration based on official prescribing information
Important Safety Information
This guide is for educational purposes only. Always follow your healthcare provider's specific instructions. If you are unsure about any step, contact your doctor or pharmacist before proceeding. Mounjaro should only be used under medical supervision.
Before You Start
Proper preparation ensures safe and comfortable injection every time.
Storage Requirements
- Store unused pens in refrigerator at 36°F to 46°F (2°C to 8°C)—do not freeze
- Keep in original carton to protect from light
- If needed, pen may be stored at room temperature (up to 86°F/30°C) for up to 21 days
- Do not use if pen has been frozen—discard immediately
Timing & Scheduling
- Inject once weekly on the same day each week
- Can be taken with or without meals—no food timing required
- If dose is missed, inject within 4 days (96 hours) then resume regular schedule
- If more than 4 days have passed, skip missed dose and inject next dose on regular day
4 Steps to Use Your Mounjaro Pen
Follow these exact steps from the official Mounjaro prescribing information for safe administration.
Choose Your Injection Site
Select one of three approved injection areas. It's important to rotate sites with each weekly dose to prevent injection site reactions and lipodystrophy.
Abdomen (Belly)
At least 2 inches away from belly button. Avoid areas with scars or stretch marks.
Thigh
Front or outer thigh area. Use fleshy part of upper leg, avoid inner thigh.
Back of Upper Arm
Outer back area of upper arm. Requires another person to administer.
Pull Off the Gray Base Cap
Check pen is locked: Ensure the lock ring shows a locked symbol before removing cap
Pull straight off: Use firm, steady pressure to remove cap—do not twist
Never replace the cap: Once removed, discard cap immediately—replacing it can damage the needle
Place Clear Base on Skin, Then Unlock
Critical Positioning Steps:
Clean the injection site: Use alcohol swab in circular motion, let dry completely (30-60 seconds)
Place flat against skin: Position clear base perpendicular to skin at 90-degree angle—not at a slant
Unlock when flat: Only when base is completely flat against skin, turn lock ring to unlock position
Press and Hold Up to 10 Seconds
Injection Sequence:
Press Purple Button Firmly
Apply steady pressure to the purple injection button. You will hear a first loud click immediately—this means the injection has started.
Continue Holding (Count to 10)
Keep pressing and holding the button. Slowly count to 10 or watch the gray plunger move down through the window. This ensures full dose delivery.
Listen for Second Click
After 5-10 seconds, you'll hear a second click and the gray plunger will be fully visible in the window—injection is complete.
Remove Pen from Skin
Lift pen straight away from injection site. The needle automatically retracts back into the pen for safety.
After Your Injection
Immediate Post-Injection Care
- Apply gentle pressure with clean gauze if slight bleeding occurs—do not rub injection site
- Small amount of liquid at injection site is normal—this is not your medicine
- A small bruise or red mark may appear—this is common and harmless
- Log injection date, time, site location, and dose in your tracking journal or app
Safe Pen Disposal
Immediately after use, place used pen in an FDA-cleared sharps disposal container. Do NOT throw in household trash or recycling.
If you don't have a sharps container, use a heavy-duty plastic container with screw-on lid (laundry detergent bottle). Label clearly: "Used Sharps - Do Not Recycle."
Troubleshooting Common Issues
What if I don't hear the second click?
Check if the gray plunger is fully visible in the window. If yes, the full dose was delivered even if you didn't hear the click. If plunger is not fully visible, contact your pharmacist or healthcare provider before administering another dose.
What if the pen was unlocked before placing on skin?
If you unlocked the pen too early, lock it again, place flat on skin, then unlock. If medicine was accidentally released, do not reuse the pen. Use a new pen and contact your healthcare provider for instructions.
What if I see air bubbles in the pen?
Small air bubbles are normal and will not affect your dose. The pen is designed to deliver the correct amount of medicine regardless of small air bubbles. Do not attempt to remove air bubbles.
What if I inject in the wrong location or miss my dose day?
If you inject in an unapproved location (such as the buttocks), the medicine may not work as effectively. Contact your healthcare provider. If you miss your scheduled dose day, inject as soon as you remember if within 4 days (96 hours). If more than 4 days have passed, skip that dose and inject on your next regularly scheduled day.
What if the pen appears damaged or frozen?
Do not use a pen that has been dropped, damaged, or frozen. Inspect the pen before each use. If the solution is cloudy, discolored, or contains particles, discard the pen and use a new one. Contact your pharmacy for a replacement.
Additional Resources
Get more support and information about using Mounjaro safely.
Video Tutorials
Watch step-by-step video demonstrations of proper injection technique
View Video GuidesPrescribing Information
Read complete FDA-approved prescribing information and safety data
Read Full InformationNeed Professional Guidance?
Our healthcare professionals can provide personalized instruction and answer any questions about using Mounjaro safely and effectively.
Medical Disclaimer
This guide is for educational purposes only and does not replace professional medical advice. Always follow your healthcare provider's specific instructions. Mounjaro (tirzepatide) is a prescription medication that should only be used under medical supervision. Report any adverse reactions to your healthcare provider immediately. For medical emergencies, call emergency services or go to the nearest emergency room.