Are there any seasonal considerations for storing Wegovy?

Yes — seasonal extremes matter. In summer, protect pens from heat; don’t leave them in cars or direct sun, and use an insulated pouch for journeys. In winter, guard against freezing (a frozen pen must not be used). Unopened pens stay refrigerated; in-use pens can usually be kept below 30 °C for the leaflet-specified period, cap on and away from light. If you suspect overheating or freezing, ask your pharmacist before using the pen.

Why temperature control matters

Wegovy (semaglutide) is a temperature-sensitive medicine. NICE TA875, MHRA product information, and NHS England’s 2025 weight-management framework all emphasise correct storage as essential for preserving potency and safety. Extreme heat or cold can damage the active ingredient or cause the solution to degrade, even if it looks normal. This may result in reduced effectiveness or injection discomfort. Because the pen is pre-filled and sealed, once the internal temperature passes its safe limit, it cannot be restored.

Summer storage: avoiding heat exposure

During warmer months, it’s important to prevent the medicine from overheating. Semaglutide should never be exposed to temperatures above 30 °C once in use, and unopened pens should remain refrigerated between 2–8 °C. NHS pharmacists caution against leaving pens in parked cars, handbags near windows, or outdoor travel bags. If travelling, keep pens in an insulated medical pouch or small cooler bag with gel packs wrapped in fabric — direct ice contact should be avoided to prevent freezing. MHRA safety notices confirm that exposure to heat above 40 °C, even briefly, can reduce stability. For flights, the pen should always travel in hand luggage rather than the hold, where temperatures fluctuate.

Winter storage: protecting against freezing

Cold weather poses the opposite risk. A frozen pen should never be used, even if thawed later. Freezing changes the structure of semaglutide and can make the injection painful or ineffective. NHS and SMC guidance both stress keeping pens away from cold-air vents or metal surfaces in fridges and avoiding outdoor exposure below freezing temperatures. During winter travel, insulated pouches also protect against cold shocks, especially during long car journeys or walks. If you suspect a pen has frozen — for example, if the solution appears cloudy or crystals form — pharmacists advise discarding it and arranging a replacement.

At-home storage routines

At home, the safest option is to store unopened pens in the main body of the refrigerator, not in the freezer compartment or the door shelves where temperature fluctuates. Once in use, pens can be kept at room temperature (below 30 °C) for up to six weeks, depending on the brand leaflet and local storage instructions. Keeping the cap on protects against light and moisture, both of which can degrade the medicine over time. NICE TA875 highlights that stability data for semaglutide rely on continuous storage under these specific conditions, making routine consistency vital.

Travelling with Wegovy

Seasonal travel adds extra variables. For summer trips, use cooling wallets or medical-grade travel cases with temperature indicators to ensure pens remain stable. Airlines generally allow these in hand luggage, accompanied by a prescription label or clinic letter. For winter travel, pack pens close to your body in an inside pocket to prevent freezing, and avoid checking them in luggage where cargo holds reach sub-zero levels. NHS clinicians recommend storing travel pens separately from those for home use so exposure time can be minimised. If in doubt, check with your pharmacist or airline for specific medication transport policies.

Spotting possible storage damage

MHRA and NHS guidelines list several visual clues that a pen may be compromised:

• The solution looks cloudy or contains particles.

• The liquid has changed colour or consistency.

• The pen has been left in excessive heat or direct sun.

• The expiry date has passed.

If any of these occur, do not use the pen. Return it to a pharmacy for advice or replacement. Using damaged medicine risks reduced effect and unpredictable absorption. NICE and SMC both underline that the appearance of the solution alone cannot guarantee stability; therefore, proper temperature control is always safer than guessing.

How seasonal variation affects daily routines

Minor temperature differences between seasons can also influence where people choose to inject or store pens at home. In summer, many prefer cooler indoor spaces for injections to reduce discomfort from warmth. In winter, injecting immediately after bringing a cold pen from the fridge can sting slightly — NHS nurses suggest holding it in your hands for a minute to warm gently before use. Consistent handling, regardless of season, helps maintain predictable comfort and absorption.

What to do if a storage issue occurs

If you think a pen has overheated or frozen, don’t inject it. Pharmacists or NHS weight-management teams can advise whether it should be replaced. It’s useful to note batch numbers in your injection log — this helps clinics identify whether multiple pens might have been exposed to the same temperature extremes. Some NHS regions now distribute digital temperature monitors or fridge thermometers for medicines like Wegovy, especially during travel or summer heatwaves.

Practical prevention checklist

NHS and MHRA guidance recommend the following all-year measures:

• Keep unopened pens refrigerated between 2–8 °C.

• Once opened, store below 30 °C, cap on, away from sunlight.

• Never freeze, overheat, or leave in a vehicle.

• Use insulated pouches for travel or outdoor days.

• Replace pens if exposure is suspected.

• Always check expiry dates before injecting.

These simple habits protect both medicine quality and user comfort year-round.

The essential point

Seasonal temperature extremes can affect Wegovy’s stability. Keep unopened pens refrigerated, protect in-use pens from heat and freezing, and use insulated storage when travelling. If unsure about temperature exposure, ask a pharmacist before injecting. NICE, NHS, MHRA, and SMC guidance all agree: consistent, careful storage keeps Wegovy safe and effective in every season.