While there's plenty of talk about the hazards of exposing insulin to heat and the importance of keeping it cool or refrigerated, it’s equally vital to grasp the risks associated with insulin freezing.
Insulin is a temperature-sensitive medication that requires protection from both extreme heat and cold.
Just as insulin that's been out of the fridge for too long or insulin that has become warm, frozen insulin becomes unsafe and ineffective for use.
In this article, we’ll tackle some key questions about insulin and freezing temperatures!
Related article: Insulin Storage Explained: Room Temperature vs. Refrigeration!
What Happens If Insulin Freezes?
While there are still some questions out there, one thing is clear: you can't freeze insulin.There’s a strong agreement among doctors, pharmaceutical companies, pharmacists, and people with diabetes on this matter. If your insulin has frozen, it’s no longer safe to use.
But what actually happens when insulin freezes? Well, first, freezing temperatures can severely compromise the integrity and effectiveness of insulin. While we all know that insulin refrigeration is necessary, excessive cold can be just as damaging as heat.
When insulin freezes, it becomes unstable. The molecules develop crystals, which is an irreversible alteration that affects their biological function. This crystallisation essentially breaks down the insulin molecule, causing it to lose both effectiveness and potency. Consequently, frozen insulin is unable to lower blood glucose levels efficiently, which can lead to serious health risks when used.
Related article: Traveling with Insulin: How to Keep it Cool or Refrigerated?
Watch on video on the topic!
At What Temperature Does Insulin Freeze?
Insulin freezes at the same temperature as water: 0°C. However, it’s wise to keep a buffer zone and store your insulin well above 2°C to prevent it from nearing its freezing point. Just like water, insulin can freeze in just a few hours!
Never store insulin at or below the freezing point of 0°C, as this could result in your insulin accidentally freezing and becoming unsafe for use.
Is Frozen Insulin Safe for Use?
No, frozen insulin is not safe for use. Even if your insulin pen or vial has only frozen briefly and then thawed, using it can significantly impact your blood sugar levels, posing serious health risks.
Let’s explore what drug manufacturers say about this matter—it's quite clear: all agree that frozen insulin should not be used:
- Novo Nordisk, the maker of Novolog fast-acting insulin aspart, states, "Unused NovoLog® should be stored in a refrigerator between 2° and 8°C. Do not store it in the freezer or directly next to the refrigerator cooling element. Do not freeze Novolog, and do not use it if it has been frozen."
- Sanofi, the manufacturer of Lantus long-acting insulin glargine, warns, "Do not allow Lantus to freeze. Do not place it in a freezer or next to a freezer pack. If you see frost or ice crystals in your Lantus solution, discard it."
- Eli Lilly, the manufacturer of Humulin, an isophane intermediate-acting insulin, advises, "Do not use Humulin R U-500 if it has been frozen."
This warning about frozen insulin applied to all types and brands of insulin!
Can You Use Thawed insulin?
The answer is a definitive no. You should never use thawed insulin. If insulin has been frozen and then returns to a liquid state, it should not be used.
It's important to understand that the freezing process irreversibly compromises the insulin’s effectiveness, making it unreliable for blood sugar regulation, even after thawing.
The risks associated with thawed insulin go beyond just reduced effectiveness. Freezing damages the structural integrity of the insulin, meaning it can no longer function properly in managing blood glucose levels. Using thawed insulin can lead to unpredictable and potentially dangerous fluctuations in blood sugar, including high risks of diabetic ketoacidosis.
A case study published in Postgrad Medicine highlights the seriousness of this issue. It details a patient who, after inadvertently defrosting frozen insulin in a microwave, required emergency care due to a complete loss of blood sugar control. This emphasizes the importance of discarding any insulin that has been frozen to avoid serious health risks.
How Can You Tell if Insulin Has Frozen?
Recognising whether insulin has frozen is essential. If you’re unsure about the state of your insulin, there are several signs to help confirm your suspicions. When insulin freezes, it will show noticeable visual changes from its usual clear appearance.
Frozen insulin often appears more solid and opaque, much like how water looks when it freezes. This transformation into a crystalline state clearly indicates that the insulin is no longer usable. If your insulin is frozen, it cannot be injected, as it won’t pass through the needle anyway.
However, determining if insulin has frozen and then thawed can be trickier. Once thawed, insulin returns to a liquid state, so look for changes in color and texture instead. Compromised or bad insulin may appear cloudy, have clumps, or contain white particles—these are all signs it may have been frozen. But keep in mind that some insulin types are naturally cloudy, so it’s important to know how your specific insulin should look!
Additionally, unusually high blood sugar readings might be an indirect indication that your insulin has frozen.
Always stay vigilant, and if you have any doubts, do not use the insulin. Instead, replace it with a fresh vial or pen from your refrigerator. The risks of using bad insulin far outweigh any potential benefits. Prioritise your health by ensuring that the insulin you use is in optimal condition for effective blood sugar control!
Dispose of frozen insulin immediately
Uh-oh, has your insulin accidentally turned into an ice cube?
First and foremost, even though it might be tempting to thaw it out and hope for the best, it’s crucial to remember that frozen insulin is not safe for your health, even if it thaws! It’s time to say farewell to that vial or pen and dispose of it properly.
You can throw away insulin vials and disposable insulin pens in the regular trash, but don’t forget to remove any needle first—this should go into a sharps container.
Protect Your Insulin From Freezing Temperatures
You might be surprised at how frequently insulin can accidentally freeze. It could happen during a power outage when your home loses heat on a frigid winter day, or if you accidentally leave your insulin in the car overnight. Whether you’re traveling through cold climates or your insulin ends up next to an ice pack in your cooling bag, there are many scenarios that can lead to frozen insulin.
- Do not store insulin near the freezer compartment. Insulin should never be stored in or near the freezer due to significant temperature fluctuations in typical household refrigerators. For optimal storage, keep insulin on the middle shelf, where temperatures are most stable.
- Use Your Body Heat to Protect Insulin in Cold Weather. Are you traveling to or living in a chilly climate? One of the simplest and most effective methods to prevent your insulin from freezing is to utilize your own body heat. Keeping your insulin close to your body can help maintain a safe temperature. You can store insulin pens or vials in your inside jacket pockets or even directly against your skin under your clothing for extra warmth.
- Watch out for your insulin pump reservoir! If you’re using an insulin pump, keep in mind that the insulin in the tubing and reservoir is also vulnerable to freezing! Insulin pumps like the Tandem T:Slim come equipped with built-in temperature sensors that alert you if they become too cold. These sensors ensure that your insulin stays safe and won’t freeze, no matter how frigid the weather gets!
- Use an Insulin Cooler with Anti-Freeze Protection. When temperatures rise above 25°C, a portable insulin cooler becomes crucial for protecting your insulin from heat. However, it’s important to be cautious—some coolers may unintentionally freeze your insulin if they aren’t designed correctly. To prevent this risk, opt for a medical-grade insulin cooler with built-in anti-freeze protection.
Insulin Coolers and Mini Fridges like those from 4AllFamily are specifically engineered for safety. These travel medicine fridges use special crystals that freeze at 2°C, which is slightly higher than insulin's freezing point of 0°C. This clever design ensures that even if your insulin comes into direct contact with the cooling element, it will always remain just above freezing!
We'd Love to Hear from You!
Do you have tips or personal stories about dealing with frozen insulin? Share your experiences! How did you handle it, and what advice would you give to others in the same situation? Let’s learn from each other and build a supportive community!
