How long does semaglutide last in the refrigerator?

What does the shelf-life figure actually mean for your pen?

The 56-day refrigerated limit applies to pens that have been removed from their original outer packaging. Before that point, pens can be stored until the expiry date printed on the carton, which could be months away. Once you open the box, the clock starts. A helpful habit: when you take a new pen from the carton, write the date on the label with a permanent marker. That 30-second check removes any guesswork and means you will never rely on memory alone.

The NHS medicines page for semaglutide confirms this refrigeration requirement and advises keeping the pen in its original carton to protect it from light. Light exposure is a secondary concern, less dramatic than freezing, but still capable of reducing potency over time. Keep the carton upright in the middle of the fridge shelf rather than in the door, where temperatures fluctuate most with each opening.

For practical detail on how the total lifespan of a single pen breaks down week by week, the full pen-lifespan guide on this site walks through dose counts alongside storage timelines. They are related questions with different answers, and it is worth reading them together.

What happens if the pen gets too cold, or too warm?

Freezing is the bigger risk. The protein structure of semaglutide can be permanently altered by ice crystal formation, even if the pen looks unchanged after thawing. There is no visual test that tells you a frozen pen is safe; the conservative and correct response is to discard it and contact your prescriber before missing a dose. If you are concerned about a pen that may have frozen, our support team can help you work through next steps.

Warmth is a slower threat. Room-temperature storage is permitted, but only for the specific period stated in the leaflet, and only below 30°C. High summer temperatures in a car, a bag left in direct sunlight, or a bathroom cabinet near a shower all carry risk. The Wegovy SmPC on the electronic Medicines Compendium sets out these conditions in full; it is freely accessible and worth bookmarking as your authoritative reference.

Related reading on the out-of-fridge window specifically is covered in the room-temperature storage guide for Wegovy, a question our prescribers hear regularly, especially from patients preparing to travel.

Does it matter which semaglutide product you are using?

Yes. Wegovy (2.4mg, and the newer 7.2mg pen approved by the MHRA in April 2026) and Ozempic are both semaglutide, but they are different licensed products with different indications and, in some cases, slightly different handling instructions. Wegovy is licensed for weight management; Ozempic is licensed for type 2 diabetes, not weight loss, and the two should never be treated as interchangeable. Always follow the leaflet that comes with your specific pen.

The newer oral form (Wegovy tablets, approved by the MHRA in June 2026) has an entirely different storage profile. The tablets require no refrigeration and can be stored at room temperature, which is one of the practical advantages they offer for some patients. If you are considering the full picture of semaglutide treatment options, the Wegovy overview page covers both the injection and the tablet alongside their licensed uses and eligibility criteria.

What should you do if you are unsure whether your pen is still usable?

When in doubt, do not inject. A pen that has been stored incorrectly (frozen, left too warm, or held beyond its 56-day in-fridge limit) may look identical to a good one. The solution is always to speak to your prescriber rather than guess. They can advise whether a dose should be delayed, whether a replacement is needed, and how to avoid a gap in treatment that could affect your progress.

At nume, every prescription goes through a GPhC-registered Independent Prescriber who reviews your case personally. If you want to understand exactly how long Wegovy can stay in the refrigerator once opened, or need guidance on how long you can keep semaglutide in the refrigerator before it should be discarded, the aftercare team handles these questions seven days a week. If you are not yet on treatment and are weighing up how a clinically supervised private service works, the consultation page sets out the process from start to dispatch. Speak to our prescribers if you have questions specific to your situation, that conversation costs nothing.