Does Mounjaro need to be refrigerated?

last updated: Nov 13, 2023

2 min read

Mounjaro (tirzepatide) is a medication prescribed to treat type 2 diabetes. It comes as a once-weekly injection in pre-filled pens that should be refrigerated. We spoke with Dr. Yael Cooperman, M.D. about how to store your Mounjaro pen. 

Mounjaro Important Safety Information: Read more about serious warnings and safety info.

Weight loss

Fad diets stop here

If appropriate, get effective weight loss treatment prescribed for your body.

Fad diets stop here
Fad diets stop here

Does Mounjaro need to be refrigerated?

Yes, Mounjaro should be kept in the refrigerator. According to the manufacturer, Eli Lilly, Mounjaro pens should be stored in a cool dark place, between 36-46° Fahrenheit (2-8° Celsius). They should not be frozen. The manufacturer also recommends keeping in mind that some areas of the refrigerator can be colder than others so it may be a good idea to store the medication in the door rather than in the back of the fridge.

That said, Mounjaro can be stored unrefrigerated for up to 21 days, but should still not be exposed to temperatures above 86° Fahrenheit (30° Celsius). That means that if you’re traveling, you can take your medication with you, but if you’re flying, you should consider packing it in your carry-on, since baggage holds in planes can descend to below-freezing temperatures. 

Also, if you leave the medication out of the fridge, it’s still important to protect it from light. You can store it in the box it came in to ensure that the medication isn’t exposed to light.

What should I do if my Mounjaro was left out of the fridge?

If your Mounjaro pen was left out of the fridge but at room temperatures not exceeding 86 degrees Fahrenheit for up to 21 days, you can use your medication normally. If the medication remains unrefrigerated for more than 21 days, the active ingredients can start to break down, making it less effective. If you accidentally leave your medication out of the fridge for too long, dispose of it and speak with your healthcare provider to get a new supply. 

Mounjaro shelf life

The shelf life of Mounjaro depends on the expiration date printed on the pen itself. If you notice that your Mounjaro pen has expired before you had a chance to use it, contact your pharmacist or healthcare provider who can tell you how to dispose of the medication and get you a refill. 

If you still have questions about your medication, you can speak with your pharmacist, or healthcare provider, or call Eli Lilly, the drug’s manufacturer, directly.


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

November 13, 2023

Written by

Yael Cooperman, MD

Fact checked by

Felix Gussone, MD

About the medical reviewer

Felix Gussone is a physician, health journalist and a Manager, Medical Content & Education at Ro.

get video check ups with qualified medical advisors to review your progress on the Body Program

$99 to get started, $145/mo for ongoing care

What's included?

Provider consultation

GLP-1 prescription (if appropriate)

Insurance concierge

Ongoing care & support

Tools to track progress

Start now – $99

Please note: The cost of medication and lab testing is not included in the Body Program

Learn more about pricing

Medication is prescribed only if appropriate.