Ozempic, Wegovy, Mounjaro and Zepbound pens belong in the fridge, and each allows a different time out of it

Days out of the fridge, by product

The rule depends on the device as much as the drug. A pen that holds several weekly doses is treated differently from one that holds a single dose, and each label sets its own clock.

Ozempic

An unused Ozempic pen goes in the refrigerator and keeps until its expiration date. The label gives it no room-temperature allowance before first use. The 56 days start once the pen is in use, and from then on it can stay in the fridge or at 59°F to 86°F.

Keep the unused pen in its original carton until it’s time for the dose, keep the cap on between uses, and protect it “from excessive heat and sunlight”, in the label’s words.

Ozempic also comes as a single-dose prefilled syringe, which follows a different rule. It’s refrigerated, but if needed it can be kept at 46°F to 86°F for up to 28 days, in its carton and away from light. Its instructions add one practical step: write down the date the syringe came out of the refrigerator, and dispose of it if it isn’t used within 28 days.

Wegovy

Wegovy’s single-dose pens and syringes are refrigerated too. If needed, and only before the cap comes off, one can be kept at 46°F to 86°F in its carton for up to 28 days.

The multi-dose FlexTouch pen works like the Ozempic pen: refrigerated before first use, then good for 56 days at 59°F to 86°F or in the fridge.

Wegovy tablets don’t go in the fridge at all. The label says to store them at 68°F to 77°F, permits excursions to 59°F to 86°F, and says to keep them in the original bottle “to protect tablets from moisture”.

Mounjaro and Zepbound

The two tirzepatide labels share one set of storage rules, nearly word for word. Every device starts in the refrigerator at 36°F to 46°F, in its carton to keep out light.

A single-dose pen or vial can, if needed, be stored unrefrigerated at no more than 86°F “for up to a total of 21 days”, and after 21 days at room temperature it’s thrown away. That’s a real difference from the Ozempic pen: a tirzepatide single-dose pen can spend time out of the fridge before it’s ever used.

Multi-dose vials and KwikPens follow a 30-day rule. Unopened, one lasts until its expiration date in the fridge, or 30 days at room temperature. Once opened it can stay in the fridge or at room temperature, and it’s thrown away after 30 days at room temperature in total, 30 days after first use, or four weekly doses, “even if there is medicine left in it”.

Heat, light and freezing

All four labels treat freezing the same way: don’t, and don’t use a pen that has been frozen. The two semaglutide labels add where not to put it in the fridge, too. Ozempic’s reads: “Do not store in the freezer or directly adjacent to the refrigerator cooling element.”

On heat, 86°F (30°C) is the ceiling. It’s the top of every room-temperature allowance in the table above, on all four labels. Only Wegovy’s instructions say what to do past it: throw the pen away if it “has been exposed to light or temperatures above 86°F (30°C)”. The Mounjaro label says “Protect MOUNJARO from heat and light”, and Zepbound’s says the same, with no threshold beyond the 86°F room-temperature limit.

The pen instructions for Ozempic and for the Wegovy FlexTouch carry the same line: “Do not leave it in a car or other place where it can get too hot or too cold.”

Light is the other constant. All four labels call for the original carton, and the Mounjaro and Zepbound labels say that’s “to protect from light”.

What the labels don’t cover

None of the four labels says anything about shipping. The FDA’s warning about GLP-1 drugs that arrive warm or with too little ice is on a separate agency page, with its 28-day rule for multiple-dose vials, both set out in buying a GLP-1 online.

These rules also belong only to the four FDA-approved products. A compounded semaglutide or tirzepatide vial has no FDA label, so none of the storage times above applies to it. Whether a seller’s price is for an approved pen or a compounded vial isn’t always on the page, and how often a seller says which is counted separately.

Sources

See the providers

Storage rules come with the drug, not the seller. The boards list who sells each molecule and what each one publishes.

• Semaglutide providersprovider board

  Readers who have settled on semaglutide and are choosing who to buy it from.

• Tirzepatide providersprovider board

  Readers who have settled on tirzepatide and are choosing who to buy it from.

• GLP-1 telehealth providersprovider board

  Readers choosing a prescriber rather than a price — who dispenses, what the plan includes, and how to leave it.

More, read from the same labels

• Semaglutide vs tirzepatidereading the label

  What the four FDA-approved labels say each molecule is, what each is approved to treat, and where the two differ.

• How they workreading the label

  The receptor each molecule switches on, what the labels say that does to appetite, blood sugar and the stomach, and why one dose lasts a week.

• Dose escalation schedulesreading the label

  The starting dose, the escalation interval and the maximum dose each label sets, and why they are not interchangeable.

• Side effect ratesreading the label

  What each label reports for nausea, vomiting, diarrhea and constipation — and the sentence every label prints above those numbers.

• Hair lossreading the label

  Which labels report hair loss, the rate against placebo where a trial measured it, and why two of them put no number on it.

• Fatigue and tirednessreading the label

  Which labels list fatigue, the rate against placebo where a trial measured it, and what each label counts as fatigue.

• Missed dose rulesreading the label

  The window each label gives for a late dose, and the minimum gap it requires when the injection day changes.

• Drug interactionsreading the label

  Insulin and sulfonylureas, oral medications, and the oral-contraceptive precaution that appears on two of these four labels and not the other two.

• Buying one onlinereading the label

  The agency's own warning signs for a telehealth GLP-1 seller, its 28-day vial rule, and what it says about drugs that arrive warm.

• Who should not take onereading the label

  The boxed warning every one of these labels carries, the two contraindications, and which warnings appear on which product.