Trouble with Your Weight Loss Injection Pen?
If your Mounjaro or Wegovy pen isn’t working as expected, it’s usually something simple that can be resolved quickly. These pens are designed to be reliable, but occasionally a small issue, like pressure inside the cartridge or a misaligned needle, can make them feel harder to use. Watch our videos on how to use the pens.
Below, you’ll find some straightforward steps to check and fix the most common issues..
How to use your Mounjaro KwikPen
How to use your Mounjaro KwikPen
When the pen feels stuck
If the dose knob won’t press down or the dial feels stiff, it’s often due to pressure building inside the pen. This isn’t a fault or a manufacturing defect, but it can make the mechanism harder to move.
Signs to look for:
- The dose knob won’t fully depress
- Dialling feels tight or doesn’t click
- The dose knob won’t turn smoothly
What to do:
Replace the needle with a new one and prime it until you see medicine at the tip of the needle. This usually clears the pressure. If you need extra needles, you can contact us or purchase them on our website.
Pen empty before four doses?
Each pen is designed to deliver four full doses. If yours runs out sooner, it could be due to overpriming or accidentally injecting a higher dose.
Even when the pen has delivered four doses, you will notice some liquid remaining inside. This is to make sure there is enough for priming so it isn’t a full dose and can’t be used. For a full guide on getting the most from each pen, see our detailed blog post on this topic.
Tips for smooth injections
Even if you have used your pen a number of times before, it’s always worth keeping these tips in mind:
- Always prime the pen to remove air and ensure accurate dosing
- Use a new needle every time to avoid blockages and reduce infection risk
- Make sure the needle is straight and firmly attached
- Avoid pressing the dose knob without a needle attached, as this adds pressure inside the cartridge
- Inject slowly and count to five before removing the needle
- Keep your pen clean and free from dust, crumbs or moisture

Still not working?
If you’ve followed all the steps and the pen still won’t work, please send us a short video. Make sure the video shows:
- The cap removed
- The needle attached
- The safety cap taken off the needle
This allows our team to see exactly what’s happening and help you find a solution quickly.
These tips are here to make your experience as smooth and stress-free as possible. If you ever feel unsure, please reach out to us – we’re here to help.


















