So: you’ve done your research, chosen Mounjaro to help you on your weight loss journey, and your first doses have arrived after your clinician has confirmed it's suitable for you.
You may have already factored in needing to set aside time to inject on the same day every week as part of your new routine. As Mounjaro comes in liquid-form, single-dose prefilled pens, an equally important first step is planning how to store and dispose of them safely. This is especially vital if you have young children, pets, or a vulnerable person living with you.
Properly storing Mounjaro is also key to keeping your medication fresh and working effectively. It’s easier than you think and you don’t need any fancy equipment, but you do need to keep an eye on a few important details to ensure you’re using Mounjaro safely.
Read on to understand how to store Mounjaro, what to do if it expires, how to take Mounjaro travelling, and how to dispose of your medication at home or on the go.
How to store unused Mounjaro pens?
Store your unused Mounjaro pens in the refrigerator between 2°C to 8°C. Before using your Mounjaro pen, check that:
- It’s in date (you can find the expiration date on the label)
- The needle is not damaged
- The medicine isn’t cloudy, discoloured, or has particles in it
Some people prefer to get a dedicated mini fridge for medication to keep it at the right temperature and free from contamination. But if that’s not feasible for you, don’t sweat it. Storing Mounjaro in your main fridge is fine.
If you keep Mounjaro in your main refrigerator, it’s a good idea to keep it away from food, so there’s less risk of spillages that could spoil your pens or vials and make them unusable. You should also avoid keeping it in the fridge door, as this is where the temperature changes the most, or at the back of the fridge where there’s a risk of it getting too cold and freezing (we’ll get into why this is bad in a moment).
Remember: always store Mounjaro out of reach of under-18s, or any other vulnerable person that may live with you.
How long can Mounjaro be out of the fridge?
When it comes to how long Mounjaro can be stored out of the fridge, there is different guidance for those in the UK and the US.
If you’re in the UK, Mounjaro pens can be stored at room temperature (up to 30°C), but only for 30 days — even if it’s still in date. So if you’ve left your Mounjaro out of the fridge overnight, there’s no need to worry.
Always keep your Mounjaro pens in a cool, dry place, in the original box and out of direct sunlight. If you take your medication out of the fridge, set a 30-day reminder on your phone so you don’t accidentally use any doses past this date.
What happens to Mounjaro if I leave it out of the fridge?
Leaving Mounjaro out of the fridge for longer than the recommended time (30 days in the UK) will cause it to be less effective because the medication will start to break down and deteriorate, so safety and sterility can’t be guaranteed.
Extreme heat or freezing temperatures from improper storage can also affect the quality and effectiveness of your medication. Plus, steam from the shower can cause condensation on your Mounjaro pens, so be mindful not to store them in a bathroom cabinet.
Can I freeze Mounjaro?
You should not freeze Mounjaro. If your medication freezes it’s no longer safe to use, even if it’s then thawed out, as the ingredients may have degraded. Degradation means it could be less effective, or you could experience unwanted side effects from ingredient toxicity.
To keep Mounjaro at a steady temperature between 2°C to 8°C:
- Use a fridge thermometer for accurate temperature readings.
- Don’t keep it at the back of the fridge (where it’s coldest), or in the door (where it’s warmest).
- Don’t store it near ice makers, cooling units, or fridge lights that cause shifts in temperature.
- Don’t put it in the freezer.
If your pen has been frozen, throw it away and use one that has been stored according to the label instructions. If this occurs, please contact your clinician for further advice.
How to dispose of Mounjaro
It’s important to know how to dispose of Mounjaro safely. As there are needles involved, you can’t throw loose pens into your household waste.
Once your pre-filled pen has been used, it’s time to throw it out. Don’t reuse your needle or share it with anyone else. Some pens can be used for four doses with a fresh needle each time before throwing the pen away. In this case, there will be an indicator of how many doses are left. If in doubt, always check the instructions on the information leaflet or packaging your Mounjaro came in.
You’ll need a sharps bin to discard of your medication properly — never dispose of Mounjaro in your household bin. If you order from Voy, we’ll ensure a sharps bin is delivered alongside your medication, and once full you can contact your local council to collect this from your home.
Does Mounjaro expire?
Yes, Mounjaro does expire. It’s super important to check the expiration date of any medication you take because using it out of date could mean the chemical composition has changed, making it much less effective.
As tempting as it might be to use medication that’s only recently expired, a change in chemical composition means there’s no guarantee that it’s safe to use either, as there could be a risk of bad bacteria growing.
We mentioned that once stored out of the fridge, Mounjaro can only be used for a short amount of time, even if it’s still in date. If it’s been too long, or your Mounjaro has expired, properly dispose of it in your sharps bin.
You can find the expiry date of Mounjaro on the label.
What if I’m travelling with Mounjaro?
When you’re off on holiday, medication is the last thing you want to be worrying about. Travelling with Mounjaro is easy as it can be out of the fridge for up to 30 days, which makes it more travel-friendly than some medications. As Mounjaro is taken once a week, you’ll usually be able to use it before the 30-day expiration, unless you’re away for a long time or you miss a dose.
If you’re travelling with Mounjaro you should take it in your carry-on bag. Keeping it in your checked-in luggage may not only risk it getting squashed and damaged, but the temperature of the plane’s luggage storage might be too cold to safely store your Mounjaro.
If you’re worried about it getting too hot or cold while travelling, invest in a mini cooler bag to keep Mounjaro at a steady, cool temperature.
Always remember to check your airline’s restrictions for taking prescribed medication on a flight, as well as the customs regulations of your destination. We recommend bringing any prescription medication in its original packaging containing the patient information leaflet, or a copy of the prescription.
Sticking to a new medication routine can be hard to get used to, but hopefully, we’ve reassured you that Mounjaro’s storage specifications won’t disrupt your day to day, even if you’re on the go. If you have more questions about Mounjaro that aren’t answered in this article, check out our Mounjaro FAQs for more advice.
Wondering if Voy’s weight loss programme is right for you? Take our quiz to find out if it’s what you might be looking for — it only takes a few minutes.
¹“Don’t Be Tempted to Use Expired Medicines.” U.S. Food and Drug Administration
, FDA, 2024, www.fda.gov/drugs/special-features/dont-be-tempted-use-expired-medicines. Accessed 25 Nov. 2024.
²“Expiration Dates - Questions and Answers.” U.S. Food and Drug Administration, FDA, 2022, www.fda.gov/drugs/pharmaceutical-quality-resources/expiration-dates-questions-and-answers. Accessed 25 Nov. 2024.
³“Mounjaro, INN-Tirzepatide Package Leaflet: Information for the Patient.” electronic medicines compendium, Sept. 2024, www.medicines.org.uk/emc/files/pil.15481.pdf. Accessed 25 Nov 2024.
⁴“Mounjaro (Tirzepatide) Injection, for Subcutaneous Use”, U.S. Food & Drug Administration, 2022, www.accessdata.fda.gov/drugsatfda_docs/label/2022/215866s000lbl.pdf. Accessed 25 Nov. 2024.
⁵Mounjaro - Tirzepatide Injection, Solution, Eli Lilly and Company, 2024, uspl.lilly.com/mounjaro/mounjaro.html#p01. Accessed 25 Nov. 2024.
⁶“Request Clinical Waste Collection.” GOV.UK, 29 June 2018, www.gov.uk/request-clinical-waste-collection. Accessed 25 Nov. 2024.
⁷“Tirzepatide.” National Institute for Health and Care Excellence, bnf.nice.org.uk/drugs/tirzepatide/#handling-and-storage. Accessed 25 Nov. 2024.
