Does Mounjaro Have to Be Kept in the Fridge?

Both Mounjaro (tirzepatide) and Wegovy (semaglutide) are prescription-only injectable medicines supplied as pre-filled pens, and both have temperature-sensitive storage requirements set out in their official product information.

Refrigerator storage (before first use)

Unopened or unused pens should be stored in a refrigerator — generally between 2°C and 8°C. They should not be frozen; if a pen has been frozen, it should not be used. Keep pens away from the freezer compartment and ice packs inside the fridge.

Room-temperature storage (in use or when travelling)

Once taken out of the fridge, a pen can typically be stored at room temperature — below approximately 30°C — for a period of time before it must be used or discarded. Check the leaflet that came with your pen or the electronic Medicines Compendium (eMC) for the specific number of days that applies to your pen, as this can vary between products and formulations.

General handling tips

• Keep pens in their original packaging to protect them from light.
• Do not leave pens in a car, on a sunny windowsill, or anywhere they may overheat.
• If you are travelling across time zones or climates, plan ahead so your pen stays within the recommended temperature range.
• If you are ever unsure whether a pen has been stored correctly, contact your prescriber or doctor or pharmacist before using it.

For more on how the medicine works and what to expect, see our overview of how Mounjaro works. You may also find it useful to read about keeping your Mounjaro pen at the right temperature and whether Mounjaro always needs refrigeration for additional context on common storage questions.

One of the most practical ways to stay on top of your Mounjaro or Wegovy routine is to log every dose as you take it — and that is exactly where GLP Trackr helps. The app's dose and injection logging feature lets you record the date, time, and strength of each injection, so you always have a clear, timestamped record of when you last injected and which pen you are currently using.

This matters for storage, too: knowing precisely when you removed a pen from the fridge means you can track how long it has been at room temperature, helping you stay within the window recommended in your leaflet rather than guessing. If you set up dose reminders in the app, you are also less likely to forget an injection and then find yourself uncertain about a pen that has been sitting out for an unexpected length of time.

Any concerns about whether a pen has been stored correctly — or any questions about your dose — should always go to your prescriber or doctor or pharmacist. GLP Trackr gives you the records to have that conversation clearly; it is not a substitute for their guidance. If you have noticed anything unusual about your pen or the medicine inside it, contact your healthcare professional before using it.

For a broader look at managing your treatment week to week, visit our guide on Mounjaro storage and your weekly routine.

Ready to keep your injection schedule organised in one place? GLP Trackr is free to try for 7 days — available on the App Store and Google Play.