Does insulin expire? How long is it good for?

Quick answer: Yes, insulin expires. It has two expiration dates: one printed on the packaging and another that starts once it's opened or removed from the fridge. How long it is good for depends on the type, how it has been stored, and whether or not it's been opened.

Living with diabetes means managing a delicate balance, especially when it comes to insulin. This life-saving hormone helps regulate blood sugar for people with both type 1 and type 2 diabetes. However, insulin is a temperature-sensitive medication with a limited shelf life, and it can go bad if not stored or used correctly.

Learn how long your insulin stays safe, what happens if it expires, and how to store or dispose of it properly.

Prefer watching over reading? You're in luck! We've got a video covering the same topic in a visual, easy-to-follow format. Check it out below!

Does Insulin Expire?

Yes, insulin expires, and it actually has two expiration dates.

• The official expiration date is printed on each pen, vial, or cartridge.

This date indicates how long the insulin will remain stable and effective when stored correctly in its unopened form.

• The "after opening" expiration starts when insulin is opened or removed from the fridge. Depending on the type, this typically ranges from 28 to 56 days.

After this period, the insulin may lose potency, and it's no longer recommended to use it.Always refer to the instructions for your specific insulin to ensure you're keeping track of this timeline and maintaining the effectiveness of your medication.

Related article: Does Insulin Need to Be Refrigerated and How to Store Your Pens and Vials Correctly?

Insulin Expiration Dates Explained

How Long Is Insulin Good For If Not Opened?

All insulins have an expiration date set by the manufacturer, usually about one year after purchase. This date is printed on the box and on each individual pen or vial. If you can't find it, your pharmacist can help.

These expiration dates are based on clinical studies showing when the medication may become unstable or lose potency.

Even if insulin is unopened, once that date passes, it is considered expired, no matter how it was stored.

Related article: Is Your Insulin Still Safe? What Happens When It's Left Out for 1 Hour or Overnight

How Long Is Insulin Good For After Opening?

Once insulin is opened or removed from the fridge, its shelf life shortens significantly. Here's a breakdown of common types of insulin:

• Lantus, Novolog, Humalog, Apidra, Basaglar - 28 days
• Humulin - 31 days
• Novolin N, Levemir, Toujeo - 42 days
• Tresiba - 56 days

Always check the instructions specific to your medication.

Insulin Expiration Chart 

Where Should Opened Insulin Be Stored?

Once opened, do not return insulin to the fridge-it should be kept at room temperature. However, avoid exposing it to temperatures over 80°F (26°C). Before opening, insulin should be kept refrigerated between 36°F (2°C) and 46°F (8°C).

Related article: Insulin Storage: 10 Common Mistakes to Avoid When Storing Your Insulin Pens and Vials

Can Insulin Go Bad?

Yes, insulin can go bad even before it reaches its expiration date. Insulin is a sensitive medication, and its effectiveness can be compromised if it's exposed to certain conditions. Exposure to high heat, freezing temperatures, light, or even contamination can cause insulin to spoil early.

Even if the insulin is still within the official expiration period, these factors can cause the insulin to degrade, making it less effective at controlling blood sugar levels.

🚨If your insulin looks cloudy (and it's not supposed to), has clumps or discoloration, don't use it, even if it's technically "within date."

Cloudiness, for instance, can be a sign that the insulin has been compromised, and clumps or discoloration indicate that it may have lost its potency. Always check your insulin before use to ensure it looks and behaves as it should. If you're unsure, discarding it and getting a fresh vial or pen is the safer option.

Related article: Insulin and Heat: How to Keep Your Supplies Safe in High Temperatures!

What Happens If You Take Expired Insulin?

It's not safe to use once insulin has expired, whether because it passed the printed date or has been open too long. Its potency can't be guaranteed, and it may no longer be effective at lowering blood sugar. Even if insulin looks okay, never take chances with expired medicine.

Related article: What to do if you run out of insulin?

What Happens If You Use Expired Insulin?

Using expired insulin is like injecting water-it simply doesn't work. This can cause:

• High blood sugar (hyperglycemia)
• Excessive thirst
• Fatigue
• Blurred vision
• Frequent urination
• Nausea
• Ketones in urine

In severe cases, it can lead to diabetic ketoacidosis (DKA) and even coma.

How Long Can Insulin Be Used After the Expiration Date?

Technically, you should never use insulin past its expiration date. That said, in an emergency, some healthcare providers and patients agree that using insulin a few days past expiration may be okay, if it has been properly stored and no alternative is available.

But this is a last resort. Always replace expired insulin as soon as possible.

Related article: TSA Rules for Diabetic Supplies: What You Need to Know Before You Travel

What to Do With Expired Insulin

How to Dispose of Expired Insulin

Follow these steps:

1. Do not use it. Once you notice it's expired, stop using it immediately.

2. Separate it from your usable insulin to avoid confusion.

3. Dispose of insulin in household trash (FDA-approved), but:

• Remove it from the original packaging.
• Mix it with an unpleasant substance (e.g., coffee grounds, garbage) to discourage children or pets.
• Remove personal info from packaging.

4. Dispose of needles and syringes in a sharps container (not regular trash).

Final Thoughts on How Long Is Insulin Good For

Understanding insulin expiration is essential for safe and effective diabetes management. Whether storing unopened insulin in the fridge or keeping track of how long a pen has been open, staying informed can make a big difference.

Key Takeaways:

Here's a quick recap of the most essential points to remember:

💉 Yes, Insulin Expires: It has two expiration dates-one printed on the label and another that starts once opened or removed from the fridge.

📦 Storage Matters: Keep unopened insulin in the fridge, and once opened, store it at room temperature below 80°F.

⏳ Use It Before It's Too Late: Opened insulin typically lasts 28-56 days depending on the brand. Always check your specific type!

🚫 Don't Risk Expired Insulin: Using it can lead to high blood sugar or serious complications like DKA. When in doubt, toss it out.

We'd Love to Hear From You!

💬 Have you ever used expired insulin by accident or come close? What happened, and how did you handle it? We'd love to hear your experience! Share your thoughts, stories, or questions in the comments below. Your insight could help someone else!

📆 Article Update History:

✅ Updated: April 17, 2025

Originally Published: November 25, 2022