Overview
If you're experiencing an issue with your Wegovy® pen, this article explains common causes, troubleshooting steps, and what support may be available. If you use Mounjaro® instead, see the separate article on faulty or compromised Mounjaro® pens, since Mounjaro® and Wegovy® pens work differently and require different troubleshooting steps.
Use this article when you want to:
Understand why your Wegovy® pen should only be primed once
Find out about common issues that can occur with a Wegovy® pen
Know what to do if your pen is leaking, faulty, or appears empty
Learn when and how to contact MedExpress about a pen issue
Why Should I Only Prime My Wegovy® Pen Once?
Wegovy® pens are designed differently to Mounjaro® pens. Your Wegovy® pen should only be flow checked (primed) once before using the first dose. After this initial flow check, the pen should not be primed again before future injections.
Priming the pen before every dose may result in insufficient medication remaining in the pen to complete all 4 doses.
What Common Issues Can Occur With a Wegovy® Pen?
Patients commonly contact MedExpress regarding:
Bent or blocked needles
Medication leaking onto the skin during injection
Lost doses
Difficulty turning the dose selector
Pens appearing empty
Dose counter not returning to "0"
What Should I Do If My Wegovy® Pen Is Not Working Properly?
Please send MedExpress's Customer Care Team:
A clear image of the pen with the cap removed
A clear image of the medication window
A description of the issue experienced
Confirmation of how many successful doses you have already used from the pen
This helps MedExpress assess the issue accurately.
What Should I Do If My Wegovy® Needle Is Blocked or Bent?
If the dose counter does not return to "0" after pressing the injection button, the needle may be blocked or damaged.
What to do:
Replace the needle with a new compatible needle
Try administering the dose again following the manufacturer instructions carefully
Hold the pen firmly against the skin for at least 6–7 seconds after the dose counter reaches "0"
If changing the needle resolves the issue and you have used additional needles during troubleshooting, you may contact MedExpress's Customer Care Team regarding needle reimbursement support.
What Should I Do If Medication Leaks During Injection?
A small amount of medication leaking onto the skin can happen if:
The needle is not attached securely
The needle is not inserted fully into the skin
The pen is removed too quickly after injection
What to do:
Ensure the needle is attached correctly
Try using a different injection site, such as the thigh or upper arm
Hold the pen against the skin for at least 6–7 seconds after the dose counter reaches "0"
Please note that leaking caused by injection technique would not usually qualify for compensation or replacement.
What Should I Do If I Believe I've Lost a Wegovy® Dose?
If you believe a dose has been lost due to a pen issue, MedExpress's team may ask for photographs of the pen to confirm how many doses remain. If the issue is determined to be caused by a confirmed device fault, compensation may be considered by MedExpress's Customer Care Team.
Please note:
Replacement eligibility depends on the number of doses already used.
Pens with 3 successful doses already used would not qualify for a replacement pen.
Any compensation or credit is assessed on a case-by-case basis.
If you are unable to complete all 4 doses from your current pen, you should remain on your current dose strength until you have completed 4 successful doses before increasing strength, in line with manufacturer guidance.
How Do I Know If My Wegovy® Pen Is Empty?
A Wegovy® pen may appear to contain medication even after all doses have been used. When fully used:
The grey plunger moves to the top of the medication window
A small amount of liquid may still remain visible
The remaining liquid is not a usable dose
You can check how many doses remain by looking at the plunger position in the medication window:
After 1 dose used (3 doses remaining): A small portion of the grey plunger is visible at one end of the medication window, with most of the window still showing clear liquid.
After 2 doses used (2 doses remaining): The grey plunger occupies roughly half of the medication window.
After 3 doses used (1 dose remaining): The grey plunger occupies most of the medication window, with only a small area of clear liquid remaining.
After 4 doses used (pen empty): The grey plunger has moved to fill almost the entire medication window. A small amount of liquid may still be visible, but this is not a usable dose.
When Should I Contact MedExpress About My Wegovy® Pen?
Contact MedExpress's Customer Care Team if:
Your pen is not functioning correctly.
You believe your pen is faulty.
You are unable to administer your medication.
Your medication appears damaged or contaminated.
You believe you have lost a dose due to a device issue.
What Happens If My Pen Needs to Be Returned for Investigation?
In some cases, MedExpress may need to arrange for the faulty or compromised pen to be returned for further investigation with the manufacturer. For this reason, please do not dispose of your pen unless you have been advised by MedExpress's Customer Care Team that it is safe to do so.
Where a return is required, MedExpress's team will provide full instructions on how to return the pen safely.