Wegovy (semaglutide) injection pens do expire, and using them beyond the printed expiry date is not recommended. As a glucagon-like peptide-1 (GLP-1) receptor agonist licensed by the MHRA for weight management, Wegovy contains a peptide hormone analogue sensitive to temperature and light. The expiry date guarantees the medicine's potency, safety, and sterility when stored correctly. Unopened pens remain effective until expiry if refrigerated at 2°C to 8°C, or for up to 6 weeks at temperatures up to 30°C. Understanding expiry dates, proper storage, and safe disposal practices ensures your treatment remains effective and safe throughout your weight management journey.
Quick Answer: Wegovy does expire and should not be used beyond the printed expiry date, as the active ingredient semaglutide may degrade, reducing effectiveness and potentially altering safety.
Yes, Wegovy does expire. Like all prescription medicines, Wegovy (semaglutide) injection pens have a defined shelf life and expiry date printed on the packaging. The expiry date indicates the last day the manufacturer guarantees the medicine's full potency, safety, and sterility when stored correctly. Using Wegovy beyond this date is not recommended, as the active ingredient may degrade, potentially reducing effectiveness or altering the medicine's safety profile.
Wegovy is a glucagon-like peptide-1 (GLP-1) receptor agonist licensed by the Medicines and Healthcare products Regulatory Agency (MHRA) for weight management in adults with obesity or overweight with weight-related comorbidities. As a peptide hormone analogue, semaglutide is sensitive to environmental conditions such as temperature and light exposure. These factors can accelerate degradation, making adherence to storage guidelines and expiry dates especially important.
It's important to understand that Wegovy pre-filled pens are single-dose, single-use devices. Each pen is designed to deliver one dose only and must be discarded after injection. The expiry date applies to unopened Wegovy pens stored under recommended conditions. Unopened pens should be stored in a refrigerator (2°C to 8°C) and remain viable until the printed expiry date. If needed, each pen may be kept at temperatures up to 30°C for up to 6 weeks before use, but must be used before the expiry date or the end of the 6-week period, whichever comes first.
Patients should never use Wegovy after the printed expiry date. Using expired medication may compromise your treatment outcomes and is not supported by clinical evidence for safety or efficacy.
Locating the expiry date on your Wegovy pen is straightforward. The expiry date is printed on both the outer carton and on the pen label itself, typically formatted as 'EXP' followed by month and year (MM/YYYY). The medicine should not be used after the last day of the stated month. Before each injection, make it a routine to verify this date, particularly if you have stored pens for some time.
Beyond checking the printed date, you should also inspect the medicine visually before each use. Wegovy solution should be clear and colourless or slightly yellow. If you notice any of the following changes, do not use the pen, even if it hasn't reached its expiry date:
Cloudiness or discolouration – the solution appears milky, cloudy, or has changed colour
Particles or crystals – visible floating particles, sediment, or crystallisation
Damage to the pen – cracks, leaks, or mechanical damage to the injection device
If you've stored your Wegovy pen outside the refrigerator, track the start date of this room-temperature storage period. Write the date you removed the pen from the refrigerator on the label or keep a record in your medication diary or smartphone. Calculate 6 weeks from this date – this becomes your 'use by' date for the unrefrigerated pen, unless the printed expiry date comes sooner.
If you're uncertain whether your Wegovy has expired or if it's safe to use, contact your pharmacist for advice. Never guess or take risks with expired medication. Pharmacists can verify expiry dates and advise on obtaining fresh supplies. For replacement prescriptions, contact your GP surgery or specialist weight management service. If you experience any unexpected side effects, report them to the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk).
Proper storage is essential to maintain Wegovy's stability and ensure it remains effective until the expiry date. Following the storage guidelines precisely helps preserve the medicine's therapeutic properties.
Wegovy pens must be stored in a refrigerator at 2°C to 8°C until use. Keep them in the original carton to protect from light. Do not freeze Wegovy, and if a pen has been frozen, it must be discarded – freezing can damage the protein structure of semaglutide, rendering it ineffective or potentially harmful. Store pens away from the freezer compartment and avoid placing them against the back wall of the refrigerator where temperatures may drop below 2°C.
If needed, each pen may be kept at temperatures up to 30°C for up to 6 weeks before use. This flexibility is particularly helpful for patients who travel or prefer not to refrigerate their current pen. However, the pen must still be protected from direct heat and light. Never leave Wegovy in direct sunlight, near radiators, or in hot environments such as cars, as temperatures above 30°C can degrade the medicine rapidly.
Keep the pen cap on to protect the medicine from light until you are ready to use it. Keep Wegovy out of sight and reach of children. When travelling, transport pens in an insulated cool bag if refrigeration isn't available, but avoid using ice packs that might freeze the medicine.
Remember that Wegovy pre-filled pens are single-use devices. After administering your dose, the entire pen should be discarded appropriately (see disposal guidance). The shelf life of Wegovy is specified in the Summary of Product Characteristics and on your packaging – always refer to the specific expiry date on your packaging rather than assuming a standard timeframe.
Using expired Wegovy is not recommended and may pose both efficacy and safety concerns. Whilst there is no official link suggesting that using slightly expired Wegovy causes immediate serious harm, the medicine's effectiveness cannot be guaranteed beyond the expiry date, and the risk-benefit profile becomes uncertain.
Reduced potency is the primary concern with expired semaglutide. As the active ingredient degrades over time, the concentration of therapeutically active semaglutide decreases. This means an expired dose may deliver less than the intended amount of medicine, potentially resulting in:
Diminished appetite suppression and reduced weight loss efficacy
Inconsistent blood levels of the medicine, disrupting the steady-state pharmacokinetics that Wegovy's once-weekly dosing is designed to achieve
While Wegovy may have effects on blood glucose, it's important to note that in the UK, it is licensed specifically for weight management, not for glycaemic control in type 2 diabetes.
Whilst serious adverse effects from using recently expired Wegovy are unlikely, degradation products could theoretically alter the medicine's safety profile. Protein-based medicines like semaglutide can break down into fragments or aggregates that may increase the risk of injection site reactions or, very rarely, immunogenic responses. However, there is limited clinical evidence documenting specific harms from expired GLP-1 receptor agonists.
If you accidentally inject expired Wegovy, monitor yourself for any unusual symptoms and contact your GP or pharmacist for advice. Report any suspected adverse reactions to the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk). Do not simply continue using expired pens – obtain a fresh prescription promptly.
From a treatment continuity perspective, using expired Wegovy may disrupt your weight management progress. The NICE guidelines for obesity management (TA875) emphasise consistent, evidence-based pharmacotherapy alongside lifestyle interventions. Compromised medication efficacy could undermine your overall treatment plan and delay achievement of your weight loss goals.
Safe disposal of expired or used Wegovy pens is essential to protect others and the environment. Never dispose of medicines in household waste or down the drain, as this can contaminate water supplies and pose risks to others who might encounter discarded sharps.
Remember that Wegovy pens are single-use devices and should be discarded after a single injection. After administering your dose, remove the needle and dispose of it in a sharps bin. The entire pen should then be disposed of according to local guidance.
Return expired, unused Wegovy pens to your pharmacy. This is the safest and most environmentally responsible disposal method. UK pharmacies operate a medicines take-back scheme and will dispose of your expired or unwanted Wegovy pens appropriately, ensuring they are incinerated at licensed facilities. You do not need to have obtained the medicine from that specific pharmacy – any community pharmacy will accept returned medicines free of charge.
Before returning pens, ensure the needle is not attached. Replace the pen cap to cover the injection site. Place the pen back in its original carton if possible, or clearly label it as 'expired medication' to avoid confusion.
For used needles, obtain a sharps bin from your pharmacy, GP surgery, or local council. Never dispose of needles in household recycling or waste bins, as this poses a serious injury and infection risk to waste handlers. Once your sharps container is full, follow your local council's sharps disposal guidance. Arrangements for sharps disposal vary across the UK – some areas offer pharmacy returns, while others require council collection services. Your pharmacist can advise on local arrangements.
Keep a disposal routine: when you receive a new Wegovy prescription, check existing stock for expired pens and return them promptly. This prevents accumulation of expired medicines at home and reduces the risk of accidentally using an out-of-date pen.
If you have questions about disposal, contact your pharmacist or local council's environmental health department. The NHS website also provides guidance on safe medicine disposal. Never give expired Wegovy to others, even if they use the same medicine – this is illegal and potentially dangerous.
Wegovy pens may be kept at temperatures up to 30°C for a maximum of 6 weeks before use, but must be used before the printed expiry date or the end of the 6-week period, whichever comes first.
Monitor yourself for unusual symptoms and contact your GP or pharmacist for advice. Report any suspected adverse reactions to the MHRA Yellow Card scheme and obtain a fresh prescription promptly.
Return expired or unused Wegovy pens to any UK community pharmacy, which operates a free medicines take-back scheme. Dispose of used needles separately in a sharps bin obtained from your pharmacy, GP surgery, or local council.
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DisclaimerThis content is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional with any medical questions or concerns. Use of the information is at your own risk, and we are not responsible for any consequences resulting from its use.
