Wegovy not kept in the fridge — does it matter, and what should you do?

You get home and find the pen sitting on the kitchen counter

It happens more than you might think. The delivery arrives, you sign for it and then the school run, a phone call or just the chaos of Tuesday afternoon means the pen stays in its bag on the counter for a few hours. Before you panic, check one thing straight away: the outer packaging or the pen itself will carry a label showing the date and time you took it out of the fridge, if you noted it. If you did not, work backwards from when the delivery arrived or when you last had it refrigerated.

The licensed semaglutide injection can spend a limited time outside refrigeration, but that window is shorter than most people assume, and it is strictly defined in the Patient Information Leaflet included with your pen. That leaflet is the authoritative source; the exact figure differs between the standard Wegovy pen formats, so do not rely on a number you read online. Look at your leaflet, check the elapsed time, then decide. That one-minute check is all it takes to know where you stand.

According to NHS guidance on semaglutide, the medicine should be kept refrigerated and protected from light. If the leaflet confirms your pen is still within its permitted out-of-fridge period, it can be used and then stored back in the fridge for any remaining doses, and our page on what happens when Wegovy has been left out of the fridge covers what to look for and how to decide. If it has exceeded the window, the safe choice is a new pen.

Why storage conditions affect whether the pen works

Semaglutide is a protein-based medicine. Like many biologics, it is stable within a defined temperature range and begins to degrade outside it. That degradation is invisible, a pen exposed to excessive heat, prolonged warmth or direct sunlight can look entirely normal and still be compromised. You cannot tell by the colour, the smell or the consistency of the solution.

Freezing causes a different problem. A pen that has been frozen (even briefly) should not be used, regardless of how short the freeze was. Ice formation can damage the protein structure of the medicine and alter how it behaves. The same applies to a pen left in a hot car in summer: if it has reached temperatures well above room temperature, treat it as unusable.

Room temperature for storage purposes means roughly 15–25°C in a normal domestic setting, not a warm kitchen, a sunny windowsill or a bathroom that steams up. If you are in any doubt about the conditions the pen was exposed to, that doubt itself is a reason to contact your prescriber rather than inject.

For a broader look at how different semaglutide products approach refrigeration, our guide to semaglutide storage covers the principles across the licensed injection formats in plain terms.

What to actually do if the window has passed

Discard the pen. That is the clinical advice, and it is straightforward even if it feels wasteful. Injecting a degraded pen does not guarantee harm, but it does mean you are injecting something that may no longer contain the right amount of active medicine, which defeats the purpose of the treatment.

Disposal matters too. Wegovy pens contain a needle and should not go in the household bin loose. A sharps container is the right way to dispose of used or spoiled pens safely; most local councils offer free collection schemes, and your pharmacy can advise on drop-off points.

Contact your prescriber or pharmacist to arrange a replacement. At nume, aftercare support is available seven days a week, so you are not left to figure this out alone. If your pen was damaged in transit or arrived outside the correct temperature range, that is also worth reporting. Our team can help you work out next steps, and if there is any question about whether a replacement is clinically appropriate, a prescriber will review it the same day.

For anyone considering starting semaglutide treatment and wanting to understand the full picture before their first pen arrives, our storage guide for new starters walks through the fridge setup, what to do on delivery day and how to handle travel.

The broader question: is this the right treatment for you?

Storage accidents are part of real-world treatment. They do not mean a medicine is too complicated or that you have done something wrong. They do mean that the support structure around your treatment matters, a prescriber who answers questions promptly, clear information on handling, and a pharmacy that gives you the tools to manage safely.

Wegovy is licensed in the UK for adults with a BMI of 30 or above, or 27 and above alongside a weight-related health condition. It is a prescription-only medicine, which means a clinical assessment comes before any dispensing, a prescriber reviews your history, not software. That review is also what makes ongoing questions like this one legitimate: you have a clinical relationship to draw on, and questions such as whether Wegovy needs to be kept in the fridge throughout its life and whether Wegovy can be kept out of the fridge for short periods are exactly the kind of practical detail your care team is there to help with.

If you are already on treatment and need to talk through a storage question, our support team is the fastest route. If you are still exploring options, the treatment overview covers how semaglutide fits into the current landscape of licensed weight-management medicines in the UK. A free consultation is the right next step when you are ready to find out whether you are clinically suitable.