One of the tricky parts of living with diabetes is dealing with insulin. This life-saving hormone allows type 1 and type 2 diabetes to control their blood sugars to keep them within normal range and avoid health complications.
But it’s a very sensitive medicine with a limited shelf life. It must be kept at specific temperatures and can quickly go bad if not properly stored.
Besides, insulin is a bit of an unusual medicine in that it has two expiration dates. Learn here how to know when your insulin expires and what to do about expired insulin.
Does insulin expire?
Yes, insulin expires. It even has two expiration dates! The first is the “official” one and is printed on each pen, vial, or cartridge. The second one isn't set as a fixed date but arrives about one month after insulin has been opened or taken out of the fridge (it may vary from 28 days to 56 days, depending on the specific type of insulin you're using).
Does insulin expire if not opened?
All insulins have an expiration date labeled on the pen, vial, or cartridge by the manufacturer. Most of the time, it’s about one year after the purchase date. You can find the expiration date on the packaging and each pen, vial, or cartridge. If you don't see it, ask your pharmacist for help.
All medications have an expiration date, and it's not chosen at random. It matches the results of thorough clinical studies and corresponds to the shelf life after which a specific medication may become unstable and unsuitable for use. It depends on the degradation mechanism of each medical product.
Passed that date, insulin’s stability cannot be guaranteed, and your insulin is considered expired whether it has been opened or not and whether it has been stored inside or outside of the fridge.
Meanwhile, remember that your insulin must be stored in the fridge, and always check the expiration date on a pen or a vial before opening it. You must also keep track of another expiration date: the one after opening your insulin container for the first time.
Related article: Insulin Pen Needle Types and Sizes, The Ultimate Guide!
Insulin expiration after opening
Before opening, your insulin must be stored at fridge temperatures (between 36°F (2°C) and 46°F (8°C).
Once opened or removed from the fridge (even briefly), insulin starts degrading and is guaranteed to stay fully efficient for a limited period (usually a month). Therefore, a new expiration process begins when you remove the cap, puncture an insulin vial, or use an insulin pen.
Then, your insulin will expire before its labeled expiration date. The new expiration usually happens within a month, but it may vary depending on specific insulins and their stability at room temperature.
- For Lantus, Novolog, Humalog, Apidra, and Basaglar, the expiration after opening is 28 days.
- For Humulin, the expiration date after opening is 31 days.
- For Novolin N, Levemir, and Toujeo, the expiration date after opening is 42 days.
- For Tresiba, the expiration date after opening is 56 days.
Always check the instructions for each insulin before use. Meanwhile, once your insulin has been opened, it must be kept at room temperature and should never be exposed to temperatures above 80°F (26°C).
So, how long is insulin good for?
To recap and make it simpler, insulin lasts:
- Until its labeled "official" expiration date if stored in the fridge and not open
- For 28 to 56 days (depending on the brand) once open or taken out of the fridge
What happens if you use expired insulin?
In both cases, past one of the two expiration dates, the manufacturers don’t guarantee the stability and efficiency of insulin and recommend not using it. Using expired insulin is not safe. Do not take any chances.
Related article: How to Keep Insulin Cool While Traveling?
Can you use expired insulin?
Whatever the reason why your insulin has expired, you should not use it past one of its two expiration dates. Expired insulin is not safe for use and can cause serious health complications.
Besides, never use an insulin that looks like it may have gone bad even if it’s still within its shelf life. Expiration dates are just one of the reasons why insulin can expire. Exposure to high temperatures, freezing, light, or even bacteria contamination in rare cases may cause your insulin to spoil faster than it should.
When in doubt, throw away your pen or vial and get a new one from the fridge.
Related article: How Long Can a Diabetic Go Without Insulin?
How long can you use insulin after it expires?
You should not use insulin after it expires. However, manufacturers, doctors, diabetes nurses, and patients themselves all agree that if insulin was stored correctly, using it a few days only after its expiration date should not pose any problem. Only do it if you have no other option, though...
Related article: What to do if you run out of insulin?
What are the symptoms of using expired insulin?
The symptoms of using expired insulin are the same as hyperglycemia, including high blood sugar, thirst, fatigue, blurred vision, frequent urination, nausea, ketones in urine, etc. It makes sense.
Expired insulin has lost part or all its potency, so it is not efficient enough anymore to lower blood sugar. In a way, injecting expired insulin is like injecting water. It simply does not work.
Related article: How to tell if insulin has gone bad?
Can expired insulin make you sick or kill you?
Injecting expired insulin should not immediately make you sick or kill you. However, the consequences of using expired insulin can be extremely severe and even life-threatening.
Because it's like injecting no insulin or a very low-potency one, your blood sugar levels will keep rising, causing prolonged hyperglycemia that could eventually lead to a Diabetic Ketoacidosis Coma.
What to do with expired insulin?
Expired insulin isn't safe for use anymore, so you must throw it away. To ensure there will be no confusion between your good pens or vials and the bad ones, we recommend disposing of insulin as soon as you notice it has expired.
Related article: Can you prefill insulin syringes? How long are they good for?
How to dispose of insulin pens and vials?
According to the U.S. Food and Drug Administration (FDA), you can throw medicines into your household trash, including “prescription and over-the-counter drugs in pills, liquids, drops, patches, and creams."
Before throwing insulin in the trash, it’s a good practice to remove it from its original container (vials or cartridges) and mix it with unpleasant substances like coffee, garbage, or others. The idea is to make it unattractive to children and pets if they empty the trash.
For privacy concerns, you may also want to remove stickers that disclose your personal information on the container.
Sharps like needles and syringes must be disposed of in sharps containers.
Related article: How to Dispose of Insulin Needles, Pens, Vials, and Syringes Safely?
Have you ever had to deal with expired insulin? What did you do?