From April 2026, the manufacturer is introducing a slightly updated version of the Mounjaro KwikPen as part of a planned change. During this transition, you may receive either the current or updated version in your treatment deliveries.
What has changed in the new pen?
The updated pen includes small visual and structural changes to help you identify when your treatment is complete:
Clearer completion marker: After your fourth and final dose, the plunger will sit near the very end of the pen window. This makes it clearer that all medication has been administered and the pen is ready to be safely discarded.
Less excess liquid: You may notice less liquid left in the pen after your final dose. The small amount previously included for priming and removing air bubbles has been reduced.
Both versions are completely safe to use and are designed to deliver exactly four doses of your prescribed medication.
Why does it look like a dose is missing?
If you have received the updated Mounjaro KwikPen, you are not missing a dose. Every version is designed to deliver exactly four doses.
The new pens contain less excess liquid, so the plunger sits near the end of the window after the fourth dose, with very little liquid remaining.
Older pens contained roughly 3 mL of liquid, with each dose measuring approximately 0.6 mL. This left a small amount of excess solution after the fourth dose.
Important safety reminders
The extra liquid in older pens was never intended for use and is not a fifth dose.
Do not attempt to extract more than four doses from a pen. The excess solution is not calibrated to deliver another dose correctly.
Do not use the liquid level in the pen window to determine how many doses remain.