If you're using Mounjaro for type 2 diabetes or for off-label weight loss, you know how handy the Mounjaro injection pens are.
Each pen comes with 4 preset doses and is designed to be incredibly user-friendly-no need to see or handle the needle, no mixing required, and a preset dose to avoid any mistakes.
But, like with everything, there can still be malfunctions, and it's not uncommon for Mounjaro pens to be defective or not work as expected-like the pen not clicking properly or the lock button failing to unlock.
Don't panic! Here's a troubleshooting guide for your Mounjaro pen malfunctions and how to get a replacement.
Related article: Does Mounjaro Need to be Refrigerated? How to Store your Pens?
Just a quick note: Mounjaro pens are different in the UK and in the USA. They work differently. We're here talking about the USA model.
Common Mounjaro Pen Malfunctions
Mounjaro autoinjector pens are available in six different strengths (2.5 mg to 15 mg) to meet individual needs. Each pen contains four preset doses, and each box contains 4 pens, sufficient for a month's treatment.
To understand what can go wrong when using Mounjaro pens, here's a quick recap on how they work:
Photo Credits: @Eli Lilly
First, remove the pen cap. Then, place the pen against your skin. Unlock it by turning the lock button. Once unlocked, press the injection button until you hear two clicks, which signal the start and completion of the injection.
Related article: How to Inject Mounjaro and Use the Pen Injector Correctly?
What can go wrong with your Mounjaro Pen
While the Mounjaro pen is designed for simplicity and ease of use, like any medical device, it's not immune to occasional hiccups.
A few malfunctions can affect the pen and impact the delivery of medication. Here are some of the most common problems you might encounter with your Mounjaro pens:
- Misfiring pen. Occasionally, the pen may not release any medication when the injection button is pressed. This could be due to a mechanical failure within the pen or an issue with the medication cartridge.
- No clicking. The Mounjaro pen is supposed to produce an audible click when the dose starts and another one when it finishes. If you don't hear these clicks, it might indicate a malfunction, which can leave you unsure whether the full dose has been administered.
- Unlock button issues. Sometimes, you might find that the unlock button on your Mounjaro pen doesn't turn. This problem can prevent you from starting the injection process as the pen remains locked, even when you're ready to administer your dose. This issue could stem from a mechanical fault in the pen's design.
- Partial dose delivery. Sometimes, the pen may release only part of the dose. This can happen if the pen or the needle is blocked for example.
- Jammed pen. In some cases, the pen's mechanism itself may become jammed, preventing it from dispensing any medication at all. This can be caused by internal damage or debris that obstructs the pen's moving parts.
- Leaking medication. If you notice medication leaking from your Mounjaro pen either before or during an injection, this could be a sign of a malfunction or a crack in the pen's body.
How to Fix a Broken or Malfunctioning Mounjaro Pen
If your Mounjaro pen appears defective or malfunctions, do not attempt a DIY repair. Misguided attempts to fix the pen can lead to incorrect dosing and potential health risks.
Unfortunately, there's not much you can do yourself when faced with a malfunctioning Mounjaro pen. The proper steps include checking what can be wrong, attempting the injection one more time, and reporting the issue if it still does not work.
Troubleshooting Tips:
- Check the pen: Inspect your Mounjaro pen for any visible damage or medication leaks.
- Make sure it's unlocked. Mounjaro pens are locked for safety. Before injecting the medication, you must turn the lock button to unlock the pen. Make sure it's unlocked before injecting.
- Ensure it's well positioned. The clear base of the Mounjaro pen must be placed flat against your skin.
- Follow the instructions step by step: Always use the pen as directed by the manufacturer. Misuse can lead to malfunctions.
Related article: What are The Best and Worst Foods to Eat While on Mounjaro?
Never Break the Pen Open
It's come to our attention that some people might resort to a risky shortcut when faced with a malfunctioning Mounjaro pen: breaking it open to manually extract the medication with a syringe. This is not a safe practice.
The Mounjaro pen is precisely engineered to deliver the correct dosage. When you break it open, there's no way to ensure you're drawing the right amount of medication. This uncertainty can lead to serious health risks, including underdosing or overdosing.
Breaking the pen also compromises the sterility of the medication. This can expose you to infections, particularly if the syringe used to withdraw the medication isn't sterile. Besides, Tirzepatide, the medication in Mounjaro pens is sensitive to environmental conditions. Exposing it to air and uncontrolled temperatures by breaking the pen could degrade its effectiveness.
If your Mounjaro pen isn't working, the safest option is to contact your healthcare provider for advice or get a replacement pen from the pharmacy or the manufacturer. Never take risks with your health by trying to DIY a solution that could end up doing more harm than good.
Remember, safety first! It's always better to wait for a proper replacement than to risk an improper dose or infection by attempting to extract the medication yourself.
Related article: How to Travel with Mounjaro: Safety Tips & Travel Cases.
Defective Mounjaro Pen Replacement by Eli Lilly
If you need a replacement for a defective Mounjaro pen, the manufacturer Eli Lilly may provide support.
Contact their customer service at the provided phone number for assistance in the USA: 1-833-807-MJRO (833-807-6576). Make sure to have accurate records of your pen's lot number and the issue encountered for a smoother replacement process.
Related article: What to Do If You Accidentally Leave Mounjaro Out of the Fridge.
Mounjaro Pen Malfunctions: FAQs
How do I know if I injected Mounjaro correctly?
A successful injection is typically confirmed by hearing two clicks-the first indicates the start, and the second confirms the completion of the injection.
Ensure you hear these 2 clicks and wait for at least 10 seconds while pressing the injection button. Another sign that you've injected Mounjaro correctly is when you see the grey plunger inside the pen. It's not visible before the injection, but only once the medicine has been administered.
What if the Mounjaro pen only clicked once?
If the pen only clicked once, it might not have delivered the full dose. Consult your healthcare provider or pharmacist for advice on how to proceed.
Is there a reset button on the Mounjaro pen?
No, the Mounjaro pen does not feature a reset button. If your pen is not functioning correctly, it should be replaced.
I did not feel the Mounjaro injection. Is that normal?
It is possible not to feel the injection due to the pen's design to minimize pain and discomfort. If you heard the 2 clicks and can see the grey plunger, the injection has been completed, even if you did not feel it.
Related article: When to Take Mounjaro: Should You Take it in The Morning or at Night?
We'd Love to Hear From You!
Do you have questions or experiences with Mounjaro pen malfunctions? Have you ever had to get a replacement from the manufacturer? Share your stories and questions in the comments below. Your insights could help others too!
