How Long Does Tirzepatide Last in the Fridge? What the Labels Say

The Zepbound and Mounjaro rows come from section 16.2, Storage and Handling, of each product's current prescribing information on DailyMed, the National Library of Medicine's label database, read on October 8, 2026 (Zepbound label; Mounjaro label). The two sections match apart from the product name. Labels are revised, so check the current version.

Protocol MD sells compounded tirzepatide, so we have a commercial interest in this topic. We do not sell Zepbound or Mounjaro.

Zepbound and Mounjaro are Eli Lilly's two FDA-approved tirzepatide products, and their labels give the same storage instruction: refrigerate at 2°C to 8°C, which is 36°F to 46°F (section 16.2). Kept in that range, the tirzepatide shelf life for either brand is the expiration date printed on the product.

For the multi-dose vial and the KwikPen the label says so directly: an unopened one can be used until the expiration date on the label if it is kept in the refrigerator (section 16.2). For the single-dose pen, the Instructions for Use tell the patient to check the pen label before each injection to confirm it has not expired.

Two more instructions in that section apply to every presentation:

• Do not freeze it. The label reads: do not freeze, and do not use if frozen (section 16.2). The label gives no thaw-and-use exception.
• Protect it from heat and light. The label says to store the product in its original carton to protect it from light (section 16.2).

Opening a multi-dose product starts a second clock. An opened Zepbound or Mounjaro multi-dose vial or KwikPen is thrown away 30 days after first use or after four weekly doses, even if there is medicine left in it (section 16.2).

How long tirzepatide can be unrefrigerated depends, for the brand-name products, on which presentation you have. All three limits come from section 16.2 of the Zepbound and Mounjaro labels, and none of them applies to a compounded vial.

• Single-dose pen or single-dose vial: 21 days. If needed, each one can be stored unrefrigerated at temperatures not to exceed 30°C (86°F) for up to a total of 21 days. The label then says to discard it.
• Unopened multi-dose vial or KwikPen: 30 days. If stored at room temperature up to 30°C (86°F), the label says to throw it away after 30 days.
• Opened multi-dose vial or KwikPen: 30 days. It may be kept in the refrigerator or at room temperature up to 30°C (86°F), and is thrown away after a total of 30 days at room temperature, 30 days after first use, or four weekly doses.

Two details matter. The 21 days are a total, so a night on the counter and a week in a suitcase draw from the same allowance. And the allowance stops at 86°F: for anything hotter the label gives no figure and says only to protect the product from heat.

How long compounded tirzepatide lasts in the fridge is set by the beyond-use date and storage directions on the vial your pharmacy dispensed. The FDA separately recommends discarding any multi-dose vial 28 days after first use. There is no general figure, which is why two vials from two pharmacies can carry different dates.

A beyond-use date is not a manufacturer's expiration date. The compounding pharmacist assigns it after weighing the preparation's microbiological risk, storage temperature, chemical stability, batch size and whether a sterility test is performed. United States Pharmacopeia Chapter 797 sets the maximum beyond-use date allowed on microbiological risk alone, and the compounder is expected to choose the shorter of that limit and the formula's chemical stability (Martin, 2018).

The storage periods on the Zepbound and Mounjaro labels describe those products as Eli Lilly makes them, and the clinical studies in section 14 of each label tested those products. Compounded tirzepatide is not FDA-approved, is not the same as the brand-name products, and was not studied in these trials. Our guide to whether Zepbound is the same as tirzepatide covers that difference in full.

What the FDA says about multi-dose compounded vials

The FDA notes that compounded GLP-1 medications may be dispensed in vials containing multiple doses, and it generally recommends that vials containing multiple doses of sterile medication be used within 28 days after the first use, because the risk of contamination increases after that. It advises consumers to discard the vial within 28 days after first use even if medication remains, and even if the compounder's instructions allow longer (FDA, content current as of October 1, 2026).

That 28-day figure is the FDA's general recommendation for multi-dose vials of sterile medication. It is not the beyond-use date of any particular product, including ours. Follow the storage directions on your own vial, never use it past its beyond-use date, and ask the dispensing pharmacy how the FDA recommendation applies to it.

Yes, tirzepatide expires, and the two kinds of product carry two kinds of date.

• Zepbound and Mounjaro carry an expiration date. The FDA has required one on prescription medicines since 1979, and describes it as a critical part of deciding whether a product is safe to use and will work as intended (FDA).
• Compounded tirzepatide expires on its beyond-use date. The pharmacy sets it for that preparation, as described above.

Does tirzepatide go bad or lose potency after that date? The FDA says expired medicines in general can be less effective or risky because of a change in chemical composition or a decrease in strength, and that past the expiration date there is no guarantee the medicine will be safe and effective.

The Zepbound and Mounjaro labels give one visual check. The solution should appear clear and colorless to slightly yellow, and the product should not be used if particulate matter or discoloration is seen (section 2.4 of the Zepbound label, section 2.2 of the Mounjaro label).

That check works in one direction only. A clear solution does not show that the product stayed within its storage limits, because the label's 21-day and 30-day limits apply whatever the liquid looks like.

A compounded preparation has its own formula, so what it should look like is a question for the pharmacy that made it.

Tirzepatide storage at home comes down to a few label instructions and one thermometer.

• Keep it at 36°F to 46°F. That is the tirzepatide storage temperature on both brand labels (section 16.2). The FDA advises keeping a home refrigerator at or below 40°F and checking it with an appliance thermometer. A thermometer is also how you learn whether yours sits inside the label's range rather than below it (FDA).
• Keep it in the original carton. Both labels say the carton protects the product from light.
• Count opened multi-dose products from first use. The label's 30 days and four weekly doses start with the first dose, so write that date on the carton.

Should you let tirzepatide warm up before injecting? The Zepbound and Mounjaro pen instructions say it is not necessary to warm the pen to room temperature. For a compounded vial, ask the pharmacy. Our guide to injection sites and technique covers what to raise with your prescriber about comfort.

For Zepbound and Mounjaro, the label's room-temperature allowance is what makes travel workable. A single-dose pen can spend up to a total of 21 days unrefrigerated at no more than 86°F, and a multi-dose vial or KwikPen up to 30 (section 16.2). Travel days count toward that total, and the instruction to protect the product from heat still applies.

At a US airport, the Transportation Security Administration allows medically necessary liquids in reasonable quantities for your trip in carry-on bags, and asks you to declare them to officers at the checkpoint for inspection (TSA). Unused syringes are allowed when accompanied by injectable medication. The TSA recommends, but does not require, that medication be labeled.

For compounded tirzepatide, the brand allowance does not carry over. Ask the dispensing pharmacy before the trip what its label permits, and keep the vial in its labeled packaging.

Many storage guides give a single number for compounded tirzepatide. The number belongs to your pharmacy, so the useful thing is the list of questions.

• What is the beyond-use date on this vial, and does it change after the first dose is drawn?
• What storage temperature does this preparation require, and does it tolerate any time outside it?
• How does the FDA's recommendation to discard a multi-dose vial 28 days after first use apply to this vial?
• If the vial is left out, frozen, or arrives warm, who do I call before taking the next dose?

The FDA tells patients to contact the compounder who made the drug, or the telehealth platform they bought it from, with any question about instructions for use or the label.

Protocol MD sells compounded tirzepatide, so read this page with that commercial interest in mind.

The Protocol MD tirzepatide protocol has three steps: an online intake that screens for the contraindications above, a review by a US-licensed physician who decides whether a prescription is appropriate, and dispensing by a licensed compounding pharmacy only if the physician approves. Protocol MD serves all 50 states. Your card is authorized at checkout and charged only if a physician approves your prescription.

On storage, our instruction to patients is the one this article gives everyone: follow the label on your vial. The beyond-use date and storage directions from the dispensing pharmacy are specific to that preparation, and no article replaces them. If you want a physician to review whether treatment is appropriate for you, start with the assessment.

Tirzepatide belongs in the refrigerator at 36°F to 46°F. Kept there, Zepbound and Mounjaro last until the expiration date on the label, with 21 days of room-temperature allowance for single-dose pens and vials, 30 days for multi-dose vials and KwikPens, and a 30-day or four-dose limit once a multi-dose product is opened. Compounded tirzepatide carries a beyond-use date assigned by its pharmacy, which differs from vial to vial, and the FDA recommends discarding a multi-dose vial 28 days after first use. Whichever you have, the label in your hand outranks any chart.