Policy On Faulty Wegovy & Mounjaro Pens – Troubleshooting Guide

Wegovy and Mounjaro help people make real, steady progress toward a healthier lifestyle. But! If a pen does not work (just in case), you should know how to troubleshoot and usually fix it.

This troubleshooting guide clearly describes what a faulty Wegovy pen or a faulty Mounjaro pen means. It also provides quick steps to try, explains when to stop, and explains how the replacement or refund policy in the UK works. Clear, practical guide to help you achieve your weight loss target so that you can stay safe and on track.

Wegovy Troubleshooting Guide

Most people find Wegovy pens easy to use once they’re familiar with the routine. Still, in some cases, small issues may arise but can usually be resolved quickly. Here are the common situations that usually have quick, practical solutions:

Wegovy Troubleshooting Guide

1. Wegovy pen not working

If your Wegovy (semaglutide) pen is not working or fails to operate:

• Check that a new needle is attached and both caps are removed.
• Allow the pen to reach room temperature before use.
• Confirm that the medicine appears clear and is within its expiry date.

If the device still fails to function, do not attempt to use it again. Proceed to report the issue to us.

2. Wegovy pen not injecting (dose isn’t delivered)

If the dose does not start or complete:

• Hold the pen flat against the skin.
• Press and hold the button for ten seconds continuously.
• Replace the needle once and repeat the procedure once only.

If there is still no injection, stop and report the device to The Care Pharmacy directly.

3. Air bubbles in your Wegovy pen

In your Wegovy pen, small air bubbles are expected and safe to inject. But! If large bubbles or frothy liquid are present:

• Do not shake the pen.
• Leave the pen at room temperature for 30 minutes.
• Do not use if the solution appears cloudy or contains particles.

Here is a clinical study that precisely demonstrates that small air bubbles don’t affect your safety. Besides, if you notice large bubbles persisting, please contact us for an assessment.

4. Leaking Wegovy pen issue

If any leak is observed:

• Confirm that the leak is not from the needle tip.
• Stop using the pen if fluid escapes from the pen body or the dose dial.
• Do not attempt to inject again with the same device.

Report the incident to the manufacturer or your pharmacy.

5. Wegovy pen button feels stiff

If the button resists movement:

• Replace the needle and try again once.
• Ensure the pen is at room temperature.
• Do not use excessive pressure or force.

If resistance persists, don’t force the pen further; mark it as faulty.

6. Slow dose delivery from your Wegovy pen

A slow injection can occur if:

• The pen is used immediately after refrigeration.
• The button is not pressed properly for the full ten seconds.
• Allow the pen to reach room temperature and ensure the injection is steady.

If you face this issue repeatedly, contact your pharmacy for review.

7. Not sure if your Wegovy dose went in

If it is unclear whether the full dose was delivered:

• Check that the dose counter has returned to zero.
• Inspect the injection site for leakage.
• Do not inject another dose. 

Seek professional advice from The Care Pharmacy before taking the next scheduled injection.

If the pen continues to malfunction or shows visible damage, stop using it. The device should then be reported under the Wegovy replacement policy in UK for manufacturer investigation and potential replacement.

What does a faulty Wegovy pen mean?

A faulty Wegovy pen is a genuine device failure that stops a full dose even when you’ve used it correctly.
These are uncommon, but here’s what qualifies:

• Pen won’t click, button stays rigid or jammed.
• Dial spins freely or won’t lock, mechanism fault.
• Leak from the main body, not the needle tip.
• Visible damage, cracks, cloudy liquid, or loose parts before use.
• Stops mid-dose, injection cuts out halfway
• Repeated issues from the same batch, more than one pen behaving the same way.

When any of these incidents occur, stop using the pen and prepare a report, then submit it through the correct channel. This ensures that your case is reviewed properly under UK medical device safety rules.

How does the Wegovy replacement policy work in the UK?

The Wegovy replacement policy in the UK ensures every suspected device fault is reviewed fairly and safely.

1. Report the issue

You will be asked to provide the batch number, expiry date, and a brief description of what went wrong. You will then receive a reference number to track the investigation.

2. Manufacturer investigation (Novo Nordisk)

Novo Nordisk reviews each report to determine whether the fault was caused by a manufacturing or mechanical defect. If a genuine fault is confirmed, a replacement pen is authorised through the manufacturer or your dispensing pharmacy. 

3. Refunds

Refunds are issued only when a confirmed device fault is verified through this process. This follows UK medical-device and pharmacy guidance set by the Medicines and Healthcare products Regulatory Agency (MHRA).

Mounjaro Troubleshooting Guide

The Mounjaro injection pen is designed for once-weekly use as Wegovy. Most Mounjaro pens function properly when used as directed, but practical issues can occasionally arise. Follow these checks before marking your pen as faulty.

1. Mounjaro Pen not working

If the pen does not begin the injection when the button is pressed:

• Confirm the needle is attached securely and both caps are removed.
• Hold the pen flat against the skin and press the button firmly until you hear a click.
• Do not remove the pen until the second click is heard and the indicator bar has stopped moving.

If the device still does not click, trying a new needle is the best solution. All Mounjaro faults are due to a slight bend in the needle.

2. Mounjaro Pen not clicking

Each injection has two audible clicks: one when it starts and one when it ends.

• If you lift too early after the first click, the dose may not finish.
• Hold the pen in place for the full ten seconds, even if you hear only one click.

Don’t try again, just contact your pharmacy and report the issue.

3. Air bubbles in your Mounjaro pen

The medicine inside the pen should always appear clear and colourless before use. But remember, like Wegovey, small air bubbles are normal and don’t affect bioavailability, but large bubbles aren’t and;

• The solution inside the Mounjaro pen should always be clear and colourless.
• Do not use the pen if the medicine appears cloudy, frozen, or discoloured.
• Store the pen between 2°C and 8°C, and never freeze.

Contact your pharmacy for advice before the next dosage.

4. Mounjaro Pen leaks during or after use

It won’t occur mostly, but if you suspect that your pen leaks during the dose or after completing your dose in a manner like;

• A small drop at the needle tip is normal after use.
• Stop using the pen if liquid leaks from the pen body, dose window, or plunger area.

Do not attempt to reuse or repair the pen. Report the fault to the manufacturer or The Care Pharmacy directly.

5. Yellow indicator does not move or stops midway

Primarily, the Mounjaro pen is affected by temperature, which impacts the injection speed, like;

• The yellow indicator bar should move through the viewing window.
•  If it doesn’t reach the end, but you held for ten seconds, the full dose was still likely delivered.
•  If it remains halfway, stop and seek advice before re-injecting.

Do not repeat the injection. Contact your pharmacist or prescriber for advice before the next scheduled dose.

6. Uncertain if the dose was given

If you are unsure whether the full dose was injected, pause before taking any further action. But remember;

• Do not use another pen; re-dosing may lead to an overdose.
• Record the batch number, date, and time of the incident for reference.

Share the recorded details and seek professional guidance from The Care Pharmacy on your next dose.

How does the Mounjaro replacement policy work in the UK?

The Mounjaro replacement policy in the UK follows a standard and safe route led by the manufacturer, Eli Lilly.

1. Report the issue to Lilly Medical

You can contact the Lilly Medical team, and they will collect basic details, log the complaint, and provide a case reference number.

2. Manufacturer investigation

Each report is reviewed by Lilly’s technical and safety team. If the pen is confirmed faulty, they authorise a replacement either directly or through your pharmacy. If the pen is working as designed, replacement or refund isn’t approved.

3. Refunds

Refunds are only offered when a confirmed device fault is verified. This aligns with UK medical device standards and MHRA guidance.

Conclusion

Wegovy and Mounjaro have made weekly injections a practical and effective option for individuals seeking steady weight loss. While faulty pens aren’t common, knowing how to troubleshoot and safely keep your treatment on track can help you avoid missed doses. 

The Care Pharmacy team is here to support you through every step, from troubleshooting and reporting faults to arranging replacements when needed.
Our goal is to make your treatment as simple, safe, and stress-free as possible, with expert pharmacy guidance you can trust week after week.

FAQs 

What to do if the Wegovy pen malfunctions?
Stop using it and contact your pharmacy or Novo Nordisk for investigation and replacement guidance.

How to reset the Wegovy pen?
Wegovy pens cannot be reset. Use a new pen for your next scheduled dose.

How to prime the Wegovy pen with a new needle?
Attach a new needle, remove both caps, and press until a small drop appears at the tip.

Why isn’t my Wegovy pen working?
Check the needle, temperature, and hold time. If it remains inactive, treat it as faulty and report the issue.

What happens if the Wegovy pen leaks?
Stop using it immediately. Leaks from the pen body indicate a fault requiring manufacturer review.

Can I skip a week of Wegovy?
If you miss a dose, take it within five days; if you skip it, continue your usual schedule.

How to test a Wegovy pen?
Never test-inject. Confirm flow by priming until a visible drop appears before your injection.

Is it normal for liquid to come out after an injection?
A small drop is normal. Large leakage indicates incomplete delivery; seek pharmacy advice from The Care Pharmacy.

Should there be an air bubble in my Wegovy pen?
Small air bubbles are normal. Do not use if the liquid is cloudy or contains large bubbles.

What happens if I accidentally inject an air bubble?
Small air bubbles are harmless under the skin. Continue as normal and seek advice if unsure.

How long can a Wegovy pen sit out?
Once opened, it can stay at room temperature for up to 28 days. Avoid heat and sunlight.

What if the Mounjaro pen needle is bent?
Do not use it. Replace with a new sterile needle before injecting.

Why does my Mounjaro pen seem jammed?
It may be blocked or faulty. Replace the needle once; if still jammed, stop and report it.