Can You Keep Mounjaro in the Fridge?

Mounjaro (tirzepatide) is a biological medicine supplied as a pre-filled injection pen. Like many biological medicines, it is sensitive to temperature extremes, which is why correct storage is important for maintaining the pen's integrity before use.

Fridge storage

Refrigerated storage — typically between 2°C and 8°C — is the primary storage condition for Mounjaro pens that have not yet been used. Keeping pens in the original carton helps protect them from light. Check your patient information leaflet for the exact temperature range specified for your product.

Room-temperature storage

According to product information, a Mounjaro pen can also be kept at room temperature for a limited period once removed from the fridge — but the permitted duration and maximum temperature are specific to the product. Check the leaflet that came with your pen for the precise timeframe, as using a pen that has been stored incorrectly or kept too long outside the fridge may affect how well it works. For detailed, up-to-date storage guidance, the Mounjaro entry on the electronic Medicines Compendium (eMC) is the authoritative reference.

What to avoid

• Do not freeze the pen — a pen that has been frozen should not be used.
• Keep the pen away from the freezer compartment and ice packs inside the fridge.
• Do not store it in direct sunlight or near a heat source.
• Once a pen has been used, follow the disposal guidance in your leaflet.

If you are unsure whether your pen has been stored correctly — for example, after a power cut or travel — speak to your prescriber or pharmacist before using it. You can also read more in our guide on what happens if Mounjaro is not kept in the fridge, and for more detail on timeframes see how long you can keep Mounjaro in the fridge.

Knowing where your pen has been stored is easier when you have a record. GLP Trackr's dose logging feature lets you log each injection with its date, time, and dose strength, so you always know exactly which pen you used and when — useful context if a storage question ever comes up in conversation with your prescriber or pharmacist.

The app's dose reminders also mean you are less likely to leave a pen out of the fridge by accident after a distracted injection day — a small habit that can make a real difference over a weekly schedule. And because GLP Trackr keeps a running history of your injections, you can bring a clear, accurate summary to any prescriber appointment rather than trying to recall details from memory.

For a broader look at how Mounjaro works and what to expect on your journey, visit our guide to how Mounjaro works. If you want to understand the specifics of storage duration, our page on how long you can store Mounjaro in the fridge goes into more detail.

Always follow the storage guidance in your patient information leaflet and the advice of your prescriber or pharmacist — they know your full situation and can advise if there is ever any doubt about a pen's condition.

Ready to keep your weekly Mounjaro routine properly organised? Download GLP Trackr free — available on the App Store and Google Play, with a 7-day trial to get started.