How Long Should You Keep Your Open Insulin Vials?
Key takeaways:
Insulin is a medication used to balance blood glucose (sugar) levels in people with diabetes. While some people use a vial and syringe, others use an insulin pen.
All types of insulin have a limited shelf life. The “expiration date” is how long the unopened insulin is good for. But once you open a vial, you have a limited time to use it. That’s the “use-by” date.
Insulin can be less effective if you don’t properly store and use it. Because of this, you’ll need to keep track of both the expiration date on the vial and when you opened it. You’ll also need to be clear on how to store your insulin so it doesn’t spoil.
Given the cost of an insulin vial, it might be tempting to cut some corners on how you use it. While it may seem wasteful to throw away expired or leftover insulin, using expired insulin comes with health and safety risks.
Expired insulin may not work as well, and your blood glucose can rise. This is because insulin is a peptide hormone, and it can spoil when it’s not stored correctly or used within a certain time.
Regardless of the type of insulin you’re using, there will be an expiration date on the vial. If stored properly, an unopened insulin vial should last until this date.
Save on popular GLP-1 Agonists
Take control of your health. With GoodRx, you may be eligible to save even more on popular treatments.
But once it’s opened and punctured, a new date applies. This “use-by” date will be different from the manufacturer’s expiration date on the vial, so you’ll need to keep track of both. And you may need to store your opened vial differently.
To avoid any issues with insulin, keep track of expiration dates, when you open a new vial, and follow manufacturer instructions. Your health depends upon it.
Categories of insulin
There are several different types of insulin — and a variety of other injectable diabetes medications. The recommendations for how long they keep varies. So learning about insulin can be confusing at first.
Here’s what you really need to know: There are five categories of injectable insulin. And as their names suggest, they differ in how long they take to start working (onset) and how long their effect lasts (duration).
Insulin category | Onset | Duration |
Rapid-acting insulin | 15 minutes | 2-4 hours |
Short-acting insulin | 30 minutes | 3-6 hours |
Intermediate-acting insulin | 1-hour | 12 hours |
Long-acting insulin | 2-4 hours | 24 hours |
Ultra-long-acting insulin | 6 hours | 36-42 hours |
How long can you keep an open insulin vial?
Just how long your open vial of insulin will be good depends on the brand. If you’re not sure, ask questions — storing and using insulin correctlycan be tricky. You can learn more by talking to a pharmacist or your care team. And you can always find more information on your pharmacy paperwork or by reading the medication insert that comes with the insulin vial.
Here’s a breakdown of how long you can use an open vial and how to properly store some common brands of insulin.
| After puncturing the vial | Storing open vials | |
|---|---|---|
| Rapid-acting insulin | ||
| Novolog (Insulin aspart) | Use within 28 days | At room temperature or in the fridge |
| Humalog (Insulin lispro) | Use within 28 days | At room temperature or in the fridge |
| Apidra (Insulin glulisine) | Use within 28 days | At room temperature or in the fridge |
| Short-acting insulin | ||
| Humulin R or Humulin R U-500 concentrated (insulin regular) | Use within 31 days | At room temperature or in the fridge |
| Novolin R (Insulin regular) | Use within 42 days | At room temperature |
| Intermediate-acting insulin | ||
| Humulin N (NPH Insulin) | Use within 31 days | At room temperature or in the fridge |
| Novolin N (NPH Insulin) | Use within 42 days | At room temperature |
| Long-acting insulin | ||
| Levemir (Insulin detemir) | Use within 42 days | At room temperature or in the fridge |
| Lantus (Insulin glargine) | Use within 28 days | At room temperature or in the fridge |
| Ultra-long-acting insulin | ||
| Insulin degludec (Tresiba) | Use within 56 days | At room temperature or in the fridge |
Best ways to store and use insulin vials
If you’re using an insulin vial, it’s recommended to store it in the refrigeratorbetween 36°F and 46°F before opening it. Once it’s opened, most insulin vials can be stored in the refrigerator or at controlled room temperature. Novolin N and Novolin R are two exceptions.
Here are some simple tips for keeping track of the day you opened your insulin:
Use a permanent marker to write the opening date on the vial.
Put a digital reminder on your smartphone.
The American Diabetes Association offers some more tips for protecting your insulin, like avoiding extreme heat (above 86°F) and extreme cold (below 36°F). This means that insulin should never be left inside of your car, stored in a freezer or near the cooling element in your refrigerator, or be left in direct sunlight.
Risks of using expired insulin
When insulin is stored incorrectly or expires, it begins to break down and become less effective. This is true whether the insulin vial is open or closed.
Using expired insulin that is less effective can lead to:
Difficulty managing blood sugars
Higher blood sugar levels than normal
Symptoms of high blood sugar, including increased urination and thirst, tiredness, and blurry vision
Diabetic ketoacidosis (DKA) with Type 1 diabetes
Don’t take a chance with your lifesaving medications. If you’re struggling to afford insulin, the American Diabetes Association is here to help you. You’re not in this alone — there are lots of resources and solutions.
What can you do with expired, open insulin vials?
Unfortunately, there’s not much you can do with open insulin vials. On average, they’re good for about 1 month. After that, you’ll need to throw them away, even if there’s insulin leftover in the vial.
What about unopened vials?
You should throw out unopened vials that are past their expiration date.
Sometimes, an unopened vial is in date but may look spoiled. For example, you may notice the insulin is discolored or has crystals inside the vial. In these cases, it’s worth taking it to your pharmacy. They may replace it. But don’t be tempted to use it.
The bottom line
Insulin vials have a limited shelf life both before you open them and after. They are also sensitive to temperature extremes and direct sunlight, so take care with how and where you store your insulin. Expired or spoiled insulin may not work as well and could mean your blood sugar levels are not managed safely.
Check the expiration date on your insulin vial before opening it. Take note of when you open a new vial, and use it within the correct time frame. And follow the storage instructions for your specific type of insulin. Reach out to your pharmacy or healthcare provider if you have any questions.
Why trust our experts?
References
American Diabetes Association. (n.d.). Insulin storage and syringe safety.
Association of Diabetes Care & Education Specialists. (2020). Pro tips (and tricks) for easier and better insulin injections.
Heinemann, L., et al. (2021). Insulin storage: A critical reappraisal. Journal of Diabetes Science and Technology.
Novo Nordisk. (2022). LEVEMIR- insulin detemir injection, solution [package insert].
Vieira, G. (n.d.). Insulin & temperature: Why it’s really important. Beyond Type 1.
