Do you have to refrigerate Wegovy, and what happens if you don't?

What the SmPC and Patient Information Leaflet actually tell you

The Wegovy SmPC, hosted on the eMC, is the document that governs how this medicine is stored and used. It specifies refrigeration at 2–8°C and states that the pen should not be frozen. If a pen has been frozen, it must be thrown away, the biological structure of semaglutide can be damaged by ice-crystal formation, and that damage is invisible to the naked eye. The pen will look perfectly normal, but the medicine inside may no longer work as expected.

Once out of the fridge, the pen can be kept at room temperature, but only up to the maximum temperature and for the duration set out in the SmPC and the Patient Information Leaflet included in your box. Those figures are the ones that count, and they can vary between product presentations, including the Wegovy 2mg pen, which has its own specific storage guidance. Rather than quote a single number here (where it might be read out of context) we always ask patients to check the leaflet that came with their specific pen. It takes thirty seconds and removes any ambiguity.

Keep pens away from direct sunlight and heat sources (a windowsill in August is not a safe spot). The pen cap should stay on when not in use. These are not precautions unique to semaglutide; they apply to most biological medicines, which are proteins that degrade under physical stress.

Fridge placement, freezing risks and everyday practicalities

A common question our prescribers hear is where exactly in the fridge to keep the pen. The door shelf is convenient but prone to temperature swings every time the fridge opens. The middle shelf, towards the back, tends to hold a steadier 2–8°C. Keep the pen away from the freezer compartment and the ice-maker duct, a pen pushed to the back of a fridge-freezer can ice up overnight without anyone noticing.

If you are unsure whether your home fridge is cold enough, a simple fridge thermometer costs a couple of pounds and is worth having. Fridges that are overloaded or have a failing seal can run warmer than their dials suggest, and if you have ever wondered whether Wegovy has to be refrigerated in the first place, the short answer is yes for any unopened pen you are not planning to use within the permitted out-of-fridge window.

For anyone trying to keep Wegovy within temperature range while out of the house, a soft insulated cool bag works well for day trips. Place the pen in a small zip-lock bag first, then cushion it from any ice pack with a folded cloth. Direct contact with an ice block can take the temperature below zero before you realise.

Once you have used a pen for the week's dose, recap it and return it to the fridge until the same time next week, and whether Wegovy has to stay refrigerated after first use is a question worth reading up on before you begin your treatment. Never recap a used needle; the pen's own cap (not a needle tip) is what goes back on.

What to do if your pen has been stored incorrectly

If you are unsure whether your pen has been frozen, left somewhere too warm, or exposed to sunlight for an extended period, do not simply use it and hope for the best. Contact your prescriber or pharmacist first. A pen that has been compromised may not cause harm in the way a contaminated medicine might, but it could fail to work, which matters when you are partway through a titration schedule.

At nume, our aftercare team is available seven days a week for exactly these situations. If your pen has been stored outside its permitted range and you need a replacement, speak to our team via the contact page. We can advise on next steps and, where clinically appropriate, arrange a review.

It is also worth noting that counterfeit weight-loss pens are a real and documented problem in the UK, the MHRA has issued public warnings about fake pens that contained the wrong medicine entirely. If your pen arrived without a temperature-controlled delivery, with packaging that looks inconsistent, or from a seller who did not require a prescription, that is a reason to pause before using it. Legitimate dispensing pharmacies ship these medicines in a way that protects cold-chain integrity from dispatch to your door.

Travelling with Wegovy: keeping your pen safe abroad and on the go

Wegovy is a once-weekly injection, so most people will need to travel with at least one pen at some point. The general principle is straightforward: the pen must stay within its permitted temperature range throughout the journey, not just at the destination.

If you are flying, keep the pen in your hand luggage rather than checked baggage, aircraft holds can drop well below freezing. Carry a copy of your prescription or a letter from your prescriber; airport security sometimes asks about injectable medicines. Declare it when asked.

Hotel minibars are notoriously unreliable for temperature, some run cold enough to freeze medicines near the cooling element. A dedicated travel fridge or a high-quality insulated pouch with a reputable cool pack is a more dependable solution for longer trips.

For anyone planning ahead, the cost of private Wegovy treatment is worth understanding before you start, since travelling with the medicine is part of the longer-term picture. You can explore treatment options and speak to a prescriber through our free consultation.