How Long Can Wegovy Be Left Unrefrigerated?

What does the SmPC actually say about Wegovy left unrefrigerated?

The Wegovy SmPC, published on the electronic Medicines Compendium (eMC), sets out the licensed storage conditions. The primary instruction is refrigeration at 2–8°C, away from the freezer compartment. Once removed from the fridge, the pen can be kept at room temperature (defined in the SmPC as not above 30°C) for a period stated in the current approved prescribing information, typically cited as up to 28 days in labelling published at launch, though you should always read your own pen's leaflet as the definitive source, since these details can be updated by the manufacturer.

The reason the window matters is that semaglutide is a peptide (a small protein) and heat causes molecular degradation long before anything looks different. A pen exposed to warmth for too long may deliver a weakened dose with no visible clue that anything is wrong. That is why the SmPC instruction is a hard limit, not a rough guide. You can find the current Wegovy prescribing information on the Wegovy SmPC on the eMC, which is updated whenever Novo Nordisk revises it.

One practical note: the 30°C ceiling assumes normal indoor conditions. A pen left in a car on a sunny afternoon can breach that temperature quickly, even in a British summer. The glove box is not storage; neither is a windowsill.

Can unrefrigerated Wegovy still be used, and how do you tell if a pen has gone off?

This is the question our prescribers hear most weeks in aftercare. The short answer is: if the pen has been out of the fridge within the permitted window and has not been exposed to excessive heat or direct sunlight, yes, it can be used. If you have lost track of how long it has been out, or it was left somewhere warm, the conservative and clinically appropriate decision is not to use it.

There is no reliable home test. Semaglutide solution should appear clear and colourless to slightly yellow, if it is cloudy, discoloured or contains particles, do not use it regardless of storage history. But a pen that looks fine may still have degraded if temperature conditions were not met, and our guide to how long Wegovy lasts unrefrigerated explains exactly what that window looks like across different scenarios. This is one reason why the NHS medicines page for semaglutide advises patients to follow storage instructions carefully and consult their pharmacist if they have doubts about a pen's integrity.

If you decide a pen should not be used, dispose of it safely in a sharps container and contact your pharmacy. Do not inject a pen you are uncertain about to avoid wasting it, the risk is not worth it.

What happens if you are travelling and Wegovy cannot be kept refrigerated?

Travel is the most common reason people find themselves managing Wegovy outside standard fridge conditions. The permitted room-temperature window gives flexibility for short trips, though anything longer needs planning. A medical-grade cooling wallet or insulated travel case can extend usable time without reaching full refrigeration, but these vary in performance and are not a substitute for a fridge on longer journeys. If you are planning a holiday or a trip with multiple nights away from reliable refrigeration, more detail on managing this safely is covered on the travelling with Wegovy unrefrigerated page.

A few practical points that often get overlooked: airport security scanners do not damage Wegovy, but you should carry it in hand luggage rather than the hold, where temperatures can drop well below freezing. A letter from your prescriber confirming the medicine is yours is worth having for international travel. And if your injection day falls mid-trip, think about what time you will be leaving and whether a dose before departure makes more sense than one taken in transit, always discuss timing adjustments with your prescriber rather than deciding alone.

For the full picture on how refrigeration and shelf life interact across different scenarios, the Wegovy refrigeration and shelf-life page covers what happens when pens are stored correctly throughout their lifespan, including the expiry date question. And if you are weighing up what Wegovy treatment involves more broadly, including costs, the Wegovy cost overview explains what a private prescription typically includes.

What should you do if your Wegovy pen has been in the cold too long, or the fridge was too cold?

Freezing is as damaging as overheating. If a pen has been accidentally frozen (say, pushed to the back of a fridge where it touched the freezer element) do not use it. Freezing causes aggregation of the peptide and can also damage the pen mechanism itself. A pen that has thawed may look identical to an undamaged one. The rule is simple: frozen equals disposed of.

Similarly, if your pen was stored correctly but the fridge malfunctioned overnight and you are not sure how long temperatures were out of range, contact your pharmacy. This is exactly the kind of aftercare question a regulated service should handle promptly. At nume, aftercare is available seven days a week for questions like this, our clinical team's details are on the prescribers page. If you have a pen that shows any mechanical issue as well as a storage concern, the Wegovy pen malfunction guidance is also worth reading before deciding how to proceed.

The broader Wegovy treatment overview, including how the prescription process works at a GPhC-registered pharmacy, is on the Wegovy treatment page. If storage questions have come up before you have even started treatment, speaking to a prescriber during a free consultation is the right place to begin, they can cover storage and aftercare alongside clinical suitability at the same time.