What Happens If You Use Expired Semaglutide?

Wondering what happens if you use expired semaglutide? For one, it can make the medication less effective — and in rare cases, it could even lead to side effects or infections if bacteria grow in the solution.

Semaglutide (a GLP-1 weight loss medication sold under brand names like Ozempic^® and Wegovy^®) does have an expiration date. After that point, the active ingredient can lose potency, and the sterile solution may no longer be guaranteed safe.

Ahead, we’ll break down the potential health risks of expired semaglutide, how long it actually lasts, warning signs your dose may have gone bad, and what to do if you’ve already used an expired pen — plus safe ways to dispose of it and get a replacement.

You open the fridge, get ready for your weekly semaglutide injection — and then notice the expiration date. While it may be tempting to ignore, it’s worth paying attention to.

“As a physician, I tell patients to not use expired semaglutide,” says Craig Primack, MD, a physician specializing in obesity medicine and senior vice president of weight management at Hims & Hers.  “After the date, potency and sterility aren’t guaranteed, so you can get lousy results and also,  a small but real infection risk at the site of injection.”

Here’s what could happen if you use expired semaglutide:

• Loss of effectiveness. Medications may not be as effective if used beyond their expiration date or beyond-use date (BUD) because their strength can decrease over time. If you’re taking semaglutide for obesity, that means it may not reduce your appetite and food cravings or increase your satiety (fullness) as much as it usually does. You may struggle to stick to nutritious food choices and healthy portion sizes without the drug’s full potency.

• Unknown side effects. The Food and Drug Administration (FDA) only tests medications for safety and stability up to their expiration date. Beyond that, it’s possible for their chemical composition to change in unpredictable ways, which could trigger unknown side effects. In other words, you may be at risk for serious adverse reactions.

• Infections. Injectable semaglutide comes in a solution. So beyond its shelf life, there’s a greater risk of contamination and bacterial or fungal growth in the liquid. Injecting it could increase your risk of infection and other complications.

Bottom line: Expired semaglutide isn’t just “less effective” — it may also carry real risks. But don’t panic. Next, we’ll walk through how long semaglutide actually lasts, how to spot when a dose has gone bad, and what to do if you’ve already used an expired pen.

So, how long is a vial of semaglutide good for? And when does an injection pen expire? Both are smart, important questions — but the answers can vary. Luckily, the expiration date is usually printed right on the vial, pen, or box.

Every semaglutide injection pen or vial has its own expiration date — always check this before you inject. You can find the semaglutide expiration date printed on the injection pen or vial, or on the medication packaging.

Besides the expiration date, make a note of the first time you use each pre-filled pen or open each vial. Once you start using a pen or vial, the clock runs a little differently:

• Ozempic^® is good for 56 days once opened, as long as it’s kept in the fridge or at room temperature.

• Compounded semaglutide is generally good for 28 days in the fridge after the first use.* Check specific storage instructions on the compounded semaglutide you’re using, as guidelines may vary.

If there’s medication left after these timeframes, it’s best to toss it and start fresh.

*Compounded semaglutide is a compounded drug and has not been FDA-approved. The FDA does not review compounded products for safety, effectiveness, or quality.

Does Ozempic^® Expire?

Yes — Ozempic^® does expire. You’ll find the expiration date on the back of the injection pen, marked as “EXP.”

Wegovy^® expires too, by the way. Its pen also has the expiration date printed as “EXP” on the label.

Whether you’re using Ozempic^® or Wegovy^® for weight management, blood sugar control, or both, always follow the instructions and never use them past the expiration date.

Does Compounded Semaglutide Expire?

Yes, compounded semaglutide also expires. The exact date can vary depending on the compounding pharmacy, but it should always be clearly labeled. Look for the expiration date on the vial of medication or on the packaging.

For more details, see our section on how long compounded semaglutide lasts in the fridge.

Does semaglutide go bad? It can. 

So, the shelf life of semaglutide isn’t the only factor to look out for to ensure it’s safe and effective. Storage matters, too — heat, freezing temps, and direct sunlight can all affect the medication.

Make it a habit to inspect your dose before every injection, even if it’s still within the expiration date.

Semaglutide should be:

• Clear

• Colorless

• Free from particles

• Never frozen

If your solution looks cloudy, discolored, frozen, or has floating particles, it might no longer be safe to use. Your best bet is to toss it and switch to a fresh dose.

When in doubt, err on the safe side and check with your prescribing healthcare professional or pharmacist. They can confirm if you need a new prescription and replacement.

And remember: Using degraded semaglutide carries the same risks as using an expired pen — it may not work as well and could cause harmful side effects.

If you’re traveling soon, here’s how to safely bring semaglutide on the road with you.

If you notice semaglutide has expired, toss it out. We know it’s tempting to use expired medication (especially when it’s expensive). But even if you’re only a few days past the before-use date, it’s not worth the risk.

If you’re unsure whether your medication is safe to use, reach out to your healthcare provider or pharmacy for advice.

First of all, try not to panic — a single dose of expired semaglutide is unlikely to cause serious harm. The more likely concern is that it may not work as intended.

Here’s what to do next:

• Monitor for side effects. Watch for unusual reactions such as redness, swelling, pain at the injection site, fever, or stomach issues.

• Check your blood sugar. If you’re using semaglutide for type 2 diabetes, keep a closer eye on your blood sugar levels to make sure they stay in range.

• Call your provider. Let your prescribing clinician or pharmacist know what happened. They can give you tailored advice and help you get a replacement dose if needed.

• Prevent future issues. Always check the expiration date before each injection, and store your medication according to instructions.

Most of the time, injecting expired doses just means reduced effectiveness. But if you notice any unusual symptoms, contact a healthcare professional right away.

“If you inject expired semaglutide, most of the time nothing good or bad will happen,” says Dr. Primack. “It likely will have less effect than usual. If you are unsure about related side effects, message your health care provider.”

When throwing out medication, dispose of needles, syringes, and injection pens in a sharps container and follow disposal guidelines for your area.

If you don’t have a sharps container, you can use an un-pierceable, closable container, like an empty laundry detergent jug or protein powder container.

Novo Nordisk, the manufacturer of Ozempic^® and Wegovy^®, has a mail-back program for expired medications. You can also check with your local pharmacy to see if they offer medication take-back programs or services.

Expired semaglutide may not be as effective or safe. It’s always advisable not to use expired medicine to protect your well-being.

Here are the key takeaways on what happens if you use expired semaglutide:

• It’s not entirely clear what happens if you use expired Ozempic^®, Wegovy^®, or compounded semaglutide, but there’s a risk that it may lose potency and could pose safety risks.

• Always check the expiration date of your medication before injecting. If it’s past its date, dispose of it safely, following the guidelines for medication disposal in your area.

• Beyond the semaglutide shelf life, check that your medication is clear, colorless, not frozen, and free from particles.

• Know how to properly store semaglutide. Most medications and supplements should be stored in a “cool, dry place,” but proper storage for semaglutide is in a refrigerator. This keeps the medication stable.

If you’re looking into weight loss medications, you can take our free online weight loss assessment to find out which treatments could work for you. Hers offers access to a range of options, including weight loss injections and oral weight loss treatments.

If you’re already taking weight loss medication through Hers, don’t forget you have unlimited 24/7 access to healthcare providers through the Hers app. A licensed medical professional can answer any questions you have about your treatment plan, from expired semaglutide and beyond.

Ozempic^® and Wegovy^® are registered trademarks of Novo Nordisk A/S. Hims, Inc. is not affiliated with or endorsed by Novo Nordisk A/S.

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.