My weight loss pen isn’t working. What should I do?

Weight loss pens like Mounjaro (tirzepatide) and Wegovy (semaglutide) are prescription medications that are designed to help you manage your weight. Like any medical device, you may encounter some issues that prevent it from working properly.

Whether this is your first time using a weight loss pen or you’re an experienced user, don’t worry - we’re here to walk you through some best practices.

Four reasons why your pen isn’t working properly

1. You’ve already administered all four doses

Both Mounjaro and Wegovy are designed to deliver exactly four doses of medication. If you’ve completed all four injections and still see liquid remaining in the pen, don’t be concerned – this residual medication is reserved for priming the pen before each use. Once you've used your four doses, it's time for a new pen.

2. The needle is not securely attached

A loose needle is one of the most common causes of pen malfunction. Before injection, make sure your needle is:

• Twisted firmly onto the pen until secure
• Completely straight (not bent or crooked)
• Free of both inner and outer caps

3. You’re using a blocked or faulty needle

Inspect your needle before each use. A blocked, bent, or damaged needle will prevent proper medication flow and cause the pen to jam. Replacing the needle with a new one can often resolve injection issues. You can purchase replacement needles via our Pharmacy Shop.

4. The pen hasn’t been primed properly

Priming ensures medication flows correctly through the needle. You should see a small drop of medication at the needle tip after priming. If no liquid appears after 2-3 priming attempts, there may be an air bubble or blockage.

Your pre-injection checklist

Make sure to always:

• Track your doses using a monthly planner
• Prime your pen before every injection to ensure the medication is flowing through the needle correctly
• Use a new needle for every injection to prevent infections and blocked needles
• Check that the needle is securely attached, and not bent or damage
• Protect your pen from materials like dirt, sand, dust, lint, crumbs, and spilled liquids

I’ve tried everything but it still doesn’t work. What should I do?

If you’ve tried all the troubleshooting steps above and your pen still isn’t working properly. Please reach out to us.

We’ll ask you to send a video demonstrating the issue with your pen and our customer support team will resolve it as quickly as possible.

We hope that you found these tips helpful and wish you the best of luck!

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