How to store Wegovy after opening: keeping your pen safe between doses

You've taken your weekly dose, where does the pen go now?

Picture the moment: you have just done your injection, the pen has clicked, and you are standing in the bathroom wondering whether it goes back in the fridge or into the bin. For Wegovy, each pre-filled pen delivers four weekly doses. That means after your first injection the pen goes back into storage (correctly) and stays there until next week.

The default place is the fridge, between 2°C and 8°C. That is the temperature range the pen was shipped in and the one that preserves semaglutide reliably. Keep it in the original carton rather than loose on a shelf; the cardboard protects it from light and stops it rolling against the fridge wall where temperatures can fluctuate.

One thing the fridge is not: a freezer. Frozen semaglutide is degraded semaglutide. If the pen has accidentally frozen (say, placed too close to the freezer compartment) it should not be used. Contact your prescriber or pharmacist before discarding it, as they can advise and arrange a replacement through the appropriate route. The detailed guidance on refrigerating Wegovy pens covers edge cases like fridge-temperature variation in more depth.

Needles should be removed after every injection and disposed of safely. Leaving a needle attached risks contamination and air entering the cartridge. A proper sharps container makes disposal straightforward and is a legal requirement for home use of medical sharps in the UK.

Taking your pen out of the fridge: the room-temperature window

Life is not always fridge-adjacent. You might inject at a friend's house, at the office, or before an early morning flight. The good news is that Wegovy pens can be kept at room temperature (up to 30°C) for a defined period once removed from the fridge. After that window closes, the pen should be used or discarded; it cannot simply be returned to the fridge indefinitely and have the clock reset.

The exact number of days at room temperature is stated in the Wegovy Patient Information Leaflet, which comes in the box. It is also published on the eMC's Wegovy SmPC entry. We do not print that figure here because pen formats can differ (the standard multi-dose pen and the newer 7.2mg single-dose pen each have their own licensed shelf-life data) and your leaflet is the version specific to what you have been prescribed.

A useful habit: write the date on the carton with a marker the day you first take a pen out of the fridge. That makes it easy to track without relying on memory. If you tend to order on a set day each month, aligning injection days with your order schedule means you are rarely working from a pen that has been out for longer than you realised.

Heat is the main enemy during room-temperature storage. A window ledge in summer, a car dashboard, or a bag left in direct sun can push ambient temperature well above 30°C quickly. Our full guide to Wegovy storage after opening covers exactly what to do in these warmer conditions, including what counts as an acceptable room-temperature window and what does not.

What happens if storage goes wrong, and when to ask for help

Mistakes happen. A pen left on the kitchen worktop over a long weekend, a power cut that takes the fridge offline, a holiday bag that sat in an airport transfer bus in 35°C heat. The NHS advises against using any medicine if you are not certain it has been stored as directed. That guidance is straightforward to follow when the instructions are clear; it is harder when you are staring at a pen and genuinely do not know.

Signs that something may be wrong: the solution looks cloudy, discoloured, or contains particles. Wegovy solution should be clear and colourless to slightly yellow. If it looks different, do not inject, the NHS tirzepatide and semaglutide medicines pages both note this as a check before use, and the same principle applies across injectable GLP-1 medicines. You can review the broader semaglutide guidance on the NHS semaglutide medicines page.

If a pen has been exposed to conditions outside its licensed storage range, the right move is to contact your prescriber or pharmacy before use. At nume, you can reach the team through our support page seven days a week. A prescriber can advise whether the pen should be replaced and, if so, ensure the clinical record is updated appropriately. It is a routine conversation for our clinical team, not something to feel awkward about raising.

It is also worth knowing about Wegovy's expiry and use-by considerations alongside storage, since they interact: a pen that is within date but has been through temperature abuse may still be compromised.

A note on pen misfires and storage-related injection problems

Occasionally, a pen that has been stored incorrectly or handled roughly may not inject correctly. Cold pens taken straight from the fridge can also be more uncomfortable and may feel as though the mechanism is stiffer than usual, so if you have ever wondered whether you can keep Wegovy in the fridge after opening and how that affects the pen before use, that guide walks through the practicalities in full. Letting the pen reach room temperature for around 30 minutes before injecting (without exceeding the room-temperature storage limit) makes the injection more comfortable and reduces the chance of a delivery problem.

If a pen appears to have misfired or not delivered the full dose, do not inject a second time to compensate. The guidance on what to do if your Wegovy pen misfires covers this in detail. In brief: note what happened, contact your prescriber, and follow the advice in your Patient Information Leaflet. Do not attempt to correct a missed dose outside of that process.

For anyone thinking about starting Wegovy or switching from another treatment, the weight-loss treatments consultation page is the place to begin. A named prescriber reviews every consultation (not software) and storage guidance, injection technique and any practical questions form part of the clinical support that follows.