Sources last read 2026-08-12

Mounjaro · Tirzepatide

Does Mounjaro need to be refrigerated?

Mounjaro is normally refrigerated at 2°C to 8°C (36°F to 46°F). A single-dose pen or vial can stay at up to 30°C (86°F) for 21 days total. Multi-dose vials and KwikPens have a 30-day room-temperature limit. After first use, discard them at the earliest of 30 days total at room temperature, 30 days after first use, or four weekly doses. Never freeze Mounjaro.

Source for this answer

Source: Eli Lilly and Company label for Mounjaro, SPL version 38, read 2026-08-12

Storage rules for your device

Match the name on your box to the device below. Check both the temperature limit and the time allowed.

Mounjaro storage conditions by device presentation, from the FDA label
Presentation	Refrigerated	Room temperature	Time allowed	After first use
Single-dose pen or single-dose vialThe four-pack of prefilled pens and the single-dose vial.	2°C to 8°C (36°F to 46°F)	not to exceed 30°C (86°F)	21 days	Not applicable
Multi-dose vial or KwikPen, unopenedThe four-dose multi-dose vial and single-patient-use KwikPen before first use.	2°C to 8°C (36°F to 46°F)	up to 30°C (86°F)	30 days	Not applicable
Multi-dose vial or KwikPen, after first useThe four-dose devices once the first dose has been taken.	2°C to 8°C (36°F to 46°F)	up to 30°C (86°F)	30 days	30 days after first use, or after four weekly doses, whichever comes first — a limit that runs alongside the room-temperature count rather than extending it.

Storage date calculator

When should I discard it?

stays on this device

Choose your Mounjaro device and enter the date below. The calculator adds the day limit from that device’s label.

Choose the device you have

Date it left the refrigerator

Nothing is saved or sent. Changing the device can change the day limit, so match the name to the device in your hand.

21-day label window

Enter the date to see when the 21-day window reaches its limit.

Temperature: not to exceed 30°C (86°F)
Label rule: Discard the single-dose pen or single-dose vial after a total of 21 days at room temperature.

This is a calendar reminder, not a temperature check. If the label counts separate periods out of the fridge, add those days together; one start date is exact only when the device stayed out continuously. If it froze, got too hot, or was out longer than you can confirm, the date alone cannot tell you whether to use it.

When the storage window ends

These conditions apply alongside the time and temperature shown above.

Single-dose pen or single-dose vial

A ceiling with no stated lower bound, matching the Zepbound label and differing from both Novo Nordisk labels.
Stated as a total of 21 days at room temperature rather than 21 consecutive days.

When the window ends: Discard the single-dose pen or single-dose vial after a total of 21 days at room temperature.

Multi-dose vial or KwikPen, unopened

Kept in the refrigerator instead, the unopened device may be used until the expiration date on the label.

When the window ends: Throw away the unopened multi-dose vial or KwikPen after 30 days at room temperature.

Multi-dose vial or KwikPen, after first use

The label permits the refrigerator or room temperature once in use, and directs storage in the original carton.

When the window ends: Three limits apply: 30 days at room temperature, 30 days after first use, or four weekly doses. Discard the device when the first limit arrives, even if medicine remains.

Freezing and light

Freezing

Do not freeze Mounjaro. Do not use it if frozen.

Light and heat

Protect Mounjaro from heat and light, and store it in the original carton to protect it from light.

Traveling with Mounjaro

Check your device’s time and temperature limits before travel. The label covers storage conditions, but it does not cover every travel question.

What the label supports

A single-dose pen or vial can stay out of the refrigerator for 21 days total at up to 30°C (86°F). Count any time already spent out of the fridge before the trip.
An in-use KwikPen or multi-dose vial may be kept at up to 30°C (86°F). Discard it at the earliest of 30 days total at room temperature, 30 days after first use, or four weekly doses.
Keep Mounjaro in its original carton to protect it from light.
The label states no lower temperature bound for the room-temperature window, but directs that the product not be frozen.

What the label does not address

Cooling bags and gel packs. The label names temperatures, never equipment.
Airport screening and X-ray. The label does not mention security screening.
Air travel, cabin pressure and checked baggage. Not addressed anywhere in the label.
Recovery after a brief excursion above 30°C (86°F). The label sets the ceiling without stating a discard rule tied to crossing it.

Questions about storing Mounjaro

Does Mounjaro need to be refrigerated?

Yes, at 2°C to 8°C (36°F to 46°F). The label also allows time at room temperature, and it differs by device: 21 days for a single-dose pen or vial, 30 days for the multi-dose vial or KwikPen.

How long can Mounjaro be left out of the refrigerator?

A single-dose pen or vial may be stored unrefrigerated at temperatures not to exceed 30°C (86°F) for up to a total of 21 days. An unopened multi-dose vial or KwikPen may be at room temperature for 30 days.

Is Mounjaro’s storage the same as Zepbound’s?

Both labels state 2°C to 8°C for refrigeration, 21 days at room temperature for single-dose devices and 30 days for multi-dose devices. Check the instructions for your own product; a future label change may affect only one brand.

What happens to Mounjaro after four doses in a KwikPen?

The label directs throwing the device away after taking four weekly doses, even if medicine is left in it — alongside the 30-days-after-first-use limit and the 30-day room-temperature count.

Can Mounjaro be frozen or used after freezing?

The label directs that Mounjaro not be frozen, and the instructions for use direct checking that the medicine is not frozen before injecting.

Does the carton matter for Mounjaro?

Yes — the label directs storing Mounjaro in the original carton to protect it from light, and protecting it from heat and light.

Does Mounjaro need to warm up before injecting?

The instructions for use state that it is not necessary to warm the pen to room temperature before an injection.

Do you have to keep Mounjaro refrigerated?

Yes — the label says 2°C to 8°C (36°F to 46°F). It also allows room temperature, and the device decides how long. A single-dose pen or vial gets 21 days; the multi-dose vial and KwikPen get 30.

The label caps room temperature at 30°C (86°F) and sets no lower bound. It also directs storing Mounjaro in its original carton, and never freezing it.

How long can tirzepatide be out of the fridge?

Mounjaro allows 21 days total out of the fridge for a single-dose pen or vial, or 30 days for an unopened multi-dose vial or KwikPen. The temperature must not exceed 30°C (86°F).

Count all time out of the fridge, including earlier trips. For an opened multi-dose vial or KwikPen, three limits apply. Discard it after 30 days total at room temperature, 30 days after first use, or four weekly doses—whichever comes first.

Why does Mounjaro only last 30 days?

Thirty days is the opened multi-dose vial or KwikPen, and three clocks run on it at once. They are 30 days total at room temperature, 30 days after first use, and four weekly doses.

Whichever runs out first ends the device, and the label says to throw it away even if medicine is left in it. A single-dose pen never reaches that rule: it goes after one dose, or after 21 days out of the refrigerator.

What is the best time of day to take Mounjaro?

The label names none. It says once weekly, at any time of day, and attaches no meal rule to the injection.

It does set two timing limits. The weekly day can move as long as two doses stay at least 3 days, or 72 hours, apart. A missed dose can be given within 4 days; past that the label says skip that week and go back to the usual day.

Storage rules for other brands

Storage limits differ by product and device. Compare the rules for each brand.

Storing ZepboundTirzepatide · Eli Lilly and Company Storing OzempicSemaglutide · Novo Nordisk Storing WegovySemaglutide · Novo Nordisk

Compare storage rules across all four labels

More about Mounjaro

Find the dose schedule and reported side effects for Mounjaro.

The Mounjaro dose scheduleEvery step, which doses you can stay on, and where the label stops Mounjaro side effects, dose by doseThe label’s own trial table, with the placebo column kept

FDA labelSPL set id d2d7da5d-ad07-4228-955f-cf7e355c8cc0

Storage information was checked against the label linked below on 2026-08-12. The version above identifies the label used.

1primary source, each with the day we read it — open the documents used on this page

MOUNJARO (tirzepatide) injection — DailyMed SPL, section 16.2 Storage and Handlingretrieved 2026-08-12FDA label

Related Mounjaro guides

What a month of Mounjaro actually costs

The Mounjaro Single-Dose Pen Savings Card advertises as little as $25 for a 1-month, 2-month or 3-month fill, and its terms expire 2026-12-31.

Mounjaro uses, dose and product guide

The highest labeled Mounjaro dose is 15 mg, read from the product label rather than the molecule in general.

Tirzepatide injection sites, timing and rotation

What the tirzepatide Instructions for Use specify, quoted rather than paraphrased.

What happens after the Ozempic window closes

3 Ozempic presentations, because the label groups its rules by device rather than by brand.

What happens after the Wegovy window closes

4 Wegovy presentations, because the label groups its rules by device rather than by brand.

How long Zepbound can sit out of the fridge

The Eli Lilly and Company label for Zepbound allows 21 or 30 days out of the fridge depending on the device.