How should Mounjaro and Zepbound be stored?

Mounjaro: US single-dose pen and vial

The cited August 2026 US FDA label says to refrigerate each single-dose pen or vial at 2–8°C. If needed, it may be kept at room temperature up to 30°C for a total of up to 21 days; the label gives discard instructions after that period. Do not freeze or use it if frozen. Keep it in the original carton to protect it from light. This example applies only to these US single-dose presentations.15

Mounjaro: multi-dose vial or KwikPen

The August 2026 US prescribing section says to refrigerate an unopened multi-dose vial or single-patient-use KwikPen at 2–8°C. If stored at room temperature up to 30°C, discard the unopened product after 30 days.

After opening, it may be kept in its original carton at 2–8°C or up to 30°C. Discard it at the first applicable limit: 30 total days at room temperature, 30 days after first use, or four weekly doses—even if medicine remains. These instructions do not extend the printed expiry date.

Ask a pharmacist how to count an uncertain storage history. Do not apply this rule to a single-dose presentation or a product from another country.15

Zepbound: US single-dose pen and vial

The August 2026 US prescribing section describes a total limit of 21 days at room temperature. But its medication guide says not to return a single-dose pen or vial to the refrigerator after room-temperature storage. The pen instructions also include that warning.

Earlier labels used different wording. The January 2026 label included the no-return instruction; the April prescribing section and pen instructions described up to 21 days unrefrigerated at no more than 30°C without repeating it.

Check the latest instructions for your exact presentation. Ask a pharmacist or manufacturer how to handle the differing instructions or an uncertain history. Do not freeze or use the product if frozen. Keep it in its original carton to protect it from light.2436

Zepbound multi-dose vial, KwikPen and travel

The August 2026 US prescribing section says to refrigerate the unopened multi-dose vial or KwikPen at 2–8°C. If it is kept at room temperature up to 30°C, discard it after 30 days. After opening, it may be refrigerated or kept up to 30°C in the original carton. Discard at the first applicable limit: 30 total days at room temperature, 30 days after first use, or four weekly doses. These instructions do not extend the printed expiry date.

Check your current exact-product label. Ask a pharmacist about unclear exposure or how to count the limits. Airport acceptance of a cooler does not prove the medicine stayed in range. See travelling with medicines that need cooling and the tirzepatide profile for benefits, risks and wider evidence.2436