Should Wegovy Be Injected Cold? Temperature Guidance for Comfort

Wegovy (semaglutide) is a GLP-1 receptor agonist licensed in the UK for weight management in adults with obesity or overweight with weight-related comorbidities. Proper injection technique and storage are essential for treatment success and patient comfort. A common question amongst patients is whether Wegovy should be injected cold directly from the refrigerator or allowed to warm to room temperature first. Understanding the impact of injection temperature on comfort and tolerability can help optimise your treatment experience whilst maintaining medication efficacy and safety throughout your weight management journey.

Wegovy Storage Requirements: Fridge vs Room Temperature

Wegovy (semaglutide) is a glucagon-like peptide-1 (GLP-1) receptor agonist licensed in the UK for weight management in adults with obesity or overweight with weight-related comorbidities. The usual maintenance dose is 2.4 mg weekly, following a dose titration schedule. Proper storage is essential to maintain the medication's stability and efficacy throughout its shelf life.

Refrigerated storage is the primary requirement for Wegovy pens. Unopened pens must be stored in a refrigerator between 2°C and 8°C, away from the freezer compartment. The pens should remain in their original carton to protect them from light. Never freeze Wegovy; if a pen has been frozen, it must be discarded as directed in the Patient Information Leaflet.

Once in use, Wegovy pens may be kept either refrigerated (2°C to 8°C) or at room temperature (below 30°C) for up to 6 weeks (42 days). This flexibility allows patients to travel or manage their medication more conveniently. However, the pen must be kept away from direct heat sources and sunlight. After 6 weeks, any remaining medication should be disposed of safely, even if the pen still contains solution. It's advisable to write the date of first use on the carton.

Key storage points:

• Store unopened pens in the refrigerator (2°C–8°C)

• Never freeze Wegovy pens

• In-use pens may be kept at room temperature (below 30°C) or refrigerated for up to 6 weeks (42 days)

• Always keep the pen cap on when not in use

• Protect from light and excessive heat

• Keep out of the sight and reach of children

Patients should check the expiry date printed on the pen label and carton before each use. If you have questions about whether your Wegovy pen has been stored correctly, contact your pharmacist or healthcare provider before injecting.

Should Wegovy Be Injected Cold or at Room Temperature?

The temperature at which Wegovy is injected can affect patient comfort and tolerability, though there is no official guidance stating that cold injection compromises the medication's efficacy. Many patients report that injecting Wegovy straight from the refrigerator causes increased discomfort, stinging, or burning sensations at the injection site.

Room temperature injection is generally preferred for patient comfort. Allowing the pen to warm naturally to room temperature before injection—typically by leaving it out of the refrigerator for 15 to 30 minutes—can help reduce injection-related discomfort. The medication remains stable during this brief period outside refrigeration, and this practice is not known to affect the drug's therapeutic effect.

The discomfort associated with cold injections may be related to the temperature difference between the cold solution and body tissue. Cold liquid entering subcutaneous tissue may stimulate temperature-sensitive nerve endings, potentially resulting in a more pronounced stinging sensation. Warmer solutions are generally better tolerated as they more closely match body temperature (approximately 37°C), though this is based on clinical experience rather than specific studies with semaglutide.

Practical recommendations:

• If desired for comfort, remove the pen from the refrigerator 15–30 minutes before your scheduled injection time

• Allow it to reach room temperature naturally—never use external heat sources

• Do not use a microwave, hot water, or direct sunlight to warm the pen

• The pen should feel neutral to touch, not cold

Some patients find that even with room-temperature injection, they experience mild discomfort. This is normal and typically resolves within minutes. However, if you experience severe pain, persistent burning, or signs of injection site reactions, contact your GP or prescribing clinician for advice.

How to Prepare Your Wegovy Pen Before Injection

Proper preparation of your Wegovy pen ensures safe, effective administration and minimises the risk of injection-related complications. Following a consistent routine helps build confidence and reduces anxiety around self-injection.

Step-by-step preparation:

1. Check the medication: Remove the pen from the refrigerator and inspect it carefully. The solution should be clear and colourless or almost colourless. Do not use the pen if the liquid appears cloudy, discoloured, or contains particles. Check the expiry date on the label.

2. Allow warming time: If desired for comfort, place the pen on a clean, flat surface at room temperature for 15–30 minutes. Do not remove the pen cap during this time, as this protects the needle and maintains sterility. Never attempt to speed up warming using external heat sources.

3. Gather supplies: Whilst the pen is warming, assemble your injection supplies: alcohol wipes, a sharps disposal container, and cotton wool or gauze if needed. Wash your hands thoroughly with soap and water.

4. Attach a new needle: Once ready to inject, remove the pen cap. Attach a new, sterile needle to the pen according to the manufacturer's instructions. Each injection requires a fresh needle to maintain sterility and ensure proper medication delivery.

5. Check the flow (first use only): For a new pen, you must perform a flow check to ensure the pen works correctly. Turn the dose selector to the flow check symbol, hold the pen with the needle pointing upward, and press the dose button until a drop appears at the needle tip.

6. Select your dose: Turn the dose selector to your prescribed dose. The dose counter should display your dose clearly. Double-check this matches your prescription.

Important safety notes:

• Never share pens between patients

• Use a new needle for every injection

• Rotate injection sites to prevent lipohypertrophy

• Follow the injection technique you were taught by your healthcare professional

• If you notice anything unusual about the pen or solution, do not inject—contact your pharmacist

Always refer to the Patient Information Leaflet provided with your medication and follow the specific training provided by your healthcare professional.

Common Injection Site Reactions and Temperature Effects

Injection site reactions are among the frequently reported adverse effects with Wegovy. According to the product information, these reactions are common (may affect up to 1 in 10 people). Understanding the relationship between injection temperature and local reactions can help patients manage these effects more effectively.

Common injection site reactions include:

• Redness (erythema) at the injection site

• Mild swelling or induration

• Bruising (ecchymosis)

• Itching or mild rash

• Temporary stinging or burning sensation

• Tenderness to touch

These reactions are typically mild to moderate in severity and resolve spontaneously within a few days. The subcutaneous injection of any medication can trigger a localised inflammatory response as the body processes the foreign substance, but this does not indicate an allergic reaction in most cases.

Temperature-related effects: Injecting cold Wegovy may exacerbate injection site discomfort and potentially increase the perception of pain. Some patients report that cold injections are associated with more pronounced stinging, which can create anxiety around subsequent doses.

Managing injection site reactions:

• Allow the pen to reach room temperature before injection if preferred for comfort

• Rotate injection sites systematically (abdomen, thigh, upper arm)

• Avoid injecting into areas with existing bruising, redness, or tenderness

• Apply gentle pressure (not rubbing) with clean gauze after injection

• Use proper injection technique—insert the needle at 90 degrees to the skin

• Avoid injecting through clothing

When to seek medical advice: Contact your GP or healthcare provider if you experience severe pain, spreading redness, warmth suggesting infection, persistent swelling beyond 48 hours, or signs of an allergic reaction. Call 999 or 112 immediately if you experience symptoms of a severe allergic reaction such as difficulty breathing, swelling of the face, lips or tongue, or severe skin rash.

You can report any suspected side effects to the MHRA Yellow Card Scheme at https://yellowcard.mhra.gov.uk or via the Yellow Card app.

Safe Handling and Storage Tips for Wegovy

Maintaining proper storage and handling practices throughout your treatment with Wegovy ensures medication safety, efficacy, and optimal therapeutic outcomes. Adherence to these guidelines also minimises waste and reduces the risk of medication errors.

Refrigerator storage best practices:

• Store Wegovy pens in the main body of the refrigerator, not in the door where temperature fluctuations are more common

• Keep pens in their original carton to protect from light

• Maintain refrigerator temperature between 2°C and 8°C—consider using a refrigerator thermometer

• Store away from the freezer compartment and avoid contact with freezer packs

• Store medicines separately from food items

• If you share a refrigerator, clearly label your medication and store it securely

• Keep out of the sight and reach of children

Travelling with Wegovy: When travelling, use an insulated cool bag with ice packs (ensuring the pen does not come into direct contact with ice). For flights, carry Wegovy in hand luggage with a letter from your prescriber confirming your need for the medication. The 6-week room temperature stability allows flexibility for short trips, but longer journeys require refrigeration arrangements.

Needle safety and disposal:

• Always use a new needle for each injection

• Never recap needles after use—this increases needlestick injury risk

• Dispose of used needles immediately in an approved sharps container

• When your sharps container is three-quarters full, seal it and return it to your pharmacy or local authority collection point

• Never dispose of needles in household waste or recycling bins

Pen disposal: Once empty or after 6 weeks of use, remove the needle and dispose of the pen according to local guidelines. Many pharmacies operate medicine return schemes.

Missed doses: If you miss a dose and it is 5 days or less since the missed dose was due, inject as soon as possible. If more than 5 days have passed, skip the missed dose and take your next injection on the regularly scheduled day.

Record keeping: Write the date of first use on the pen carton and maintain a record of your injection dates, sites used, and any reactions experienced. This information is valuable for your healthcare team in monitoring treatment response and tolerability. If you have concerns about storage conditions, contact your prescriber or pharmacist for guidance rather than making assumptions about medication safety.

Scientific References

1. Wegovy 0.25 mg, FlexTouch solution for injection in pre-filled pen - Summary of Product Characteristics.
2. Wegovy FlexTouch 0.25 mg, 0.5 mg, 1 mg, 1.7 mg and 2.4 mg solution for injection in pre-filled pen - Patient Information Leaflet.
3. Semaglutide - British National Formulary.
4. GLP-1 receptor agonists: reminder of the potential side effects and to be aware of the potential for misuse.

Frequently Asked Questions