Can expired insulin hurt you

6 Mistakes You Might Be Making With Insulin Supplies

If you’re like most people, you’re probably not giving your insulin medication all the proper care it needs. And that could cause an issue, since improperly stored insulin can lose potency, making it less effective at lowering your blood sugar levels, says Shannon Knapp, RN, CDE, the manager of diabetes education at Cleveland Clinic in Ohio.

In fact, about 25 percent of people who use insulin store it improperly, according to research published in the September 2016 issue of the journal Diabetes & Metabolic Syndrome. The study also found that fewer than half of the participants properly mixed their insulin before taking it, and more than 90 percent improperly disposed of their syringes.

Are you storing and taking your insulin correctly? Learn more about these and other common insulin mistakes, and ways to avoid them.

Mistake No. 1: Losing track of expiration dates. Expired insulin may not control your blood sugar as well as it’s supposed to, according to Vanessa Ghaderi, MD, chief of endocrinology at Kaiser Permanente South Bay Medical Center in Harbor City, California. “When insulin expires, it begins to break down, which means it becomes less effective,” she explains.

Storing unopened insulin in the fridge can help preserve it until its printed expiration date — just be sure to keep the vials that will expire first toward the front of your refrigerator shelf so that they’re the easiest to access, she suggests.

Once opened (i.e., the seal has been punctured), insulin is only good for a limited time. How long can vary depending on the type of insulin you use; it can be as short as 10 days or as many as 56 days. Make sure you know how long the type of insulin you use lasts; ask your pharmacist or another healthcare professional if you’re unsure.

When you open a new bottle, consider writing the date directly on it in large numbers so that you can easily keep track of how long you’ve been using it, Dr. Ghaderi suggests.

And remember: Any open vial or pen should be kept at room temperature — avoid storing it in areas that get too hot or cold.

Mistake No. 2: Storing insulin on the refrigerator door. If insulin is stored on the door, it will be more likely to move around every time you open and close the fridge. (Although you should gently roll your insulin to help mix it, lots of shaking isn’t ideal.) “Shaking the bottle can cause the insulin particles to stick to the vial itself, which can sometimes make it look frosted, and reduces the effectiveness of the insulin withdrawn from the vial,” Ghaderi says. Vigorous shaking can also cause clumping or create threads in the insulin.

Mistake No. 3: Using insulin that has an unusual appearance. “NPH insulin (a type of intermediate-acting insulin) should look uniformly cloudy after being gently rolled,” but all other types of insulin should be clear, Ghaderi says. If you spot insulin that appears to be frosted or discolored, or has threads or clumps, return it to the pharmacy for a replacement vial or pen. The insulin won’t be as effective, which can negatively impact your blood sugar control.

Mistake No. 4: Confusing short-acting and long-acting insulins. These two medications work in different ways, so it’s important to keep them straight. Try color-coding your vials, or consider storing them in two separate places, Ghaderi recommends. One suggestion: Keep the short-acting insulin in a kitchen cupboard if you take it before meals, and the long-acting insulin in the bedroom if you take it at bedtime, Knapp says. Or request one type of insulin in a vial and another in a pen.

If managing both types of insulin is overwhelming, Ghaderi suggests talking to your doctor about using a pre-mixed insulin that contains both types.

Mistake No. 5: Re-using syringes. Generally speaking, you should use a new pen needle or insulin syringe for every injection to both minimize pain and decrease infection risk. If you’re worried about costs, talk to your doctor about whether or not re-using syringes is a safe choice for you, as well as how to prevent infections from this practice. Your doctor may also be able to provide alternative suggestions for saving money on your diabetes medications and supplies.

Mistake No. 6: Disposing of needles improperly. When it’s time to discard your syringes, be sure to do so safely. Invest in a tool that carefully clips and stores the needle so no one else can use them. Don’t cut it with scissors, which can send the needle flying and can hurt someone, or get lost, according to the American Diabetes Association.

If you don’t feel comfortable destroying your needles, be sure to recap the syringe and store it in an opaque bottle or box that securely closes. Then contact your local refuse company or city or county waste authority to find out how to safely dispose of needles in your area.

Diabetes Forecast

Roger P. Austin, MS, RPh, CDE, responds:

For you to get consistent, predictable results when using insulin, carefully follow the insulin manufacturer’s recommended storage conditions.

What to Know:

Each vial of insulin or box of insulin pens comes with instructions about how to properly store that particular product. Be sure to read and follow these recommendations. As long as vials or pens are stored unopened in the refrigerator (at 36 to 46 degrees Fahrenheit), they are good until the expiration date on the container. Questions about the insulin’s potency start when you open the vial or pen and begin to use it.

Find Out More:

Opened vials of the following insulins and mixtures are stable for 28 days either at room temperature (defined by manufacturers as 77 to 86 degrees) or in a refrigerator (36 to 46 degrees): insulin glargine (Lantus), insulin glulisine (Apidra), insulin aspart (NovoLog), insulin lispro (Humalog), Novolin-N, Humulin-N, Novolin-R, Humulin-R, and mixtures of insulin (Novolin 70/30, Humulin 70/30, NovoLog Mix 70/30, Humalog Mix 75/25, and Humalog Mix 50/50). Opened vials of insulin detemir (Levemir) are stable for up to 42 days at the recommended conditions. Insulin should not be allowed to freeze; if vials or pens are found to be frozen, they should be discarded and replaced with fresh supplies.


Shuttling opened insulin vials between refrigeration and room temperature does not appear to affect the insulin’s potency under these conditions and time periods. However, manufacturers of insulin pens do not recommend storage in a refrigerator once a pen is opened and in use.

Protect insulin from exposure to light and extremes of temperature above and below those noted. Insulin should never be stored in a vehicle, or on windowsills or ledges, where it can be exposed to such conditions.

When traveling, keep insulin on your person or in your carry-on bag. Insulin placed in suitcases that are transported in cargo holds of aircraft, boats, and buses or in car trunks may be exposed to damaging temperature extremes.

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General Rules

  • To ensure that your insulin remains effective, stable and undamaged you should discard your ‘in use’ insulin after 28days, whether in a vial or cartridge.
  • Insulin that is not in use should be stored in the refrigerator. If refrigeration is not possible, it can be kept at room temperature for 28 days.
  • The in use vial may be kept at room temperature for 28 days.
  • In use cartridges should be kept at room temperature and SHOULD NOT be kept in the refrigerator.
  • Insulin has a ‘use by’ date as well as an expiry date.

The advice about storing insulin may differ from one manufacturer to another and so we have obtained information from the various companies:

Wockhardt UK, formerly CP Pharmaceuticals Ltd – manufacturers of natural pork and beef insulins:

“Our recommendation is that a single vial may be used repeatedly over a 3 month period, as long as the vial is maintained at the correct storage temperature of 2 to 8 degrees C.

If the vial is stored outside the refrigerator then this period of use should be reduced to 28 days. This also assumes that the vials are appropriately stored and are used under normal conditions . Insulin in cartridges is stable for up to 4 weeks once open if stored at 25 degrees C. We do not recommend that ‘in use’ cartridges are stored in the refrigerator.”

Novo Nordisk Pharmaceuticals Ltd – manufacturers of synthetic insulins, ‘human’ and analogues

No information supplied

Eli Lilly – Manufacturers of synthetic insulins – ‘human’ and anaolgues.

“Our Humulin range has regulatory approval for in-use out of the fridge for 28 days. We have also performed our own in-house studies, however these were also completed after 28 days. Therefore, we do not have any data on in-use of Humulin vials after 28 days and thus, although we have no information to suggest that there is any problem with in-use vials stored in the fridge after 28 days, without data to support this we currently can only recommend in-use for 28 days.”

Patients should always discard their ‘in use’ insulins after 28 days as a necessary precaution

Why is this important?
There are no insulins that mimic the human body’s production of insulin in response to food intake. Diabetes is not an easy condition to live with and people with diabetes are individuals with different hormonal and metabolic rates. Each person responds to insulin in different ways.

There are many variables that affect diabetic control, such as:

  • Diet and exercise
  • Lifestyle
  • Fears of low blood sugars
  • Emotions and stress

Diabetes will remain a difficult and complex condition until we are provided with better ‘tools’ with which to control it. Until then it is important that we rule out anything which could affect our diabetic control. This must include ruling out the possibility that our insulin has started to break down so that it is less potent. This results in it being absorbed and moved around the body differently, so affecting blood glucose levels.

It is also important to realise that if we have been using ‘old’ insulin that has gone off, with a change to a new fresh fully effective vial there is a greater chance of a severe hypo at the changeover time.

Maintaining healthy blood sugar levels, especially when you have type 1 or type 2 diabetes, is critical. As such, the effectiveness of your insulin pens is an important matter of safety. Like many medications, the effectiveness of insulin wears off with time, especially after the container is opened. But how long insulin remains effective can vary depending on the brand. Here are some tips to help you decide when to throw out that pen and start a new one.

Why is using expired insulin risky?

Depending on how much insulin you need with each dose, you may still have insulin left in your pen by the time you reach its expiration date. And while it might seem wasteful to throw out unused insulin, it’s important to do so because expired insulin can actually do you more harm than good.

The effectiveness of expired insulin is hard to predict. Using insulin past the manufacturer’s expiration date can cause your blood glucose to be higher than expected if you stick to the same dosing you’ve been using all along.

High blood sugar can cause symptoms like thirst, fatigue, blurry vision and a frequent need to urinate. If your blood sugar is extremely high, you may even feel nauseous and faint. And underlying all of these symptoms is the potential for organ damage with uncontrolled diabetes.

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How long are insulin pens good for?

There are several different types of injectable insulins and diabetes medications, and recommendations for how long they keep can vary. These are guidelines for some of the most popular injectable diabetes medications.

Rapid-acting insulins

  • Novolog FlexPen: use within 28 days after first use
  • Novolog cartridge (for use in a reusable pen): use within 28 days after first use
  • Humalog KwikPen: use within 28 days after first use
  • Humalog cartridge (for use in a reusable pen): use within 28 days after first use
  • Apidra SoloStar: use within 28 days after first use

Intermediate-acting insulins

  • Humulin N KwikPen: use within 14 days after first use

Long-acting insulins

  • Lantus SoloStar: use within 28 days after first use
  • Toujeo SoloStar: use within 28 days after first use
  • Levemir FlexTouch: use within 42 days after first use

Other diabetes medications in pens

  • Bydureon (single-dose pen): use immediately once the medication has been mixed
  • Byetta: pen should be discarded 30 days after initial use
  • SymlinPen: pen should be discarded 30 days after initial use
  • Trulicity (single-dose pen): each pen can be used until the expiration date on the carton
  • Victoza: pen should be discarded 30 days after initial use

What’s the best way to store insulin?

Insulin pens that are in use should be kept at room temperature (between 56ºF and 80ºF). If you buy several pens at a time to save money, the remaining pens should be stored in the refrigerator (at a temperature of 36ºF to 46ºF) to maximize their shelf life.

Pro-tip: Don’t store insulin in the fridge door because the temperature there can fluctuate when you open and close the door. The center shelf of the refrigerator is often ideal. Also, refrigerator thermostats can be inaccurate, so consider using a thermometer instead to keep track of the temperature.

Cold insulin can sometimes be painful to inject, so when you’re about ready to open your next pen, take it out ahead of time so it’s ready for your next injection.

Follow these additional tips to make sure your insulin is safe and effective:

  • Only store insulin at room temperature or in the fridge—never in extreme heat (like a hot car) or extreme cold (like the freezer). Heat, light and freezing temperatures will make insulin break down. So, even if you thaw insulin after it was frozen, do not use it. Be sure to toss it out and open a new pen that was stored in safe conditions.
  • Only use insulin that has not yet expired. When you’re ready to use your insulin pen, mark down the date you opened it, keep it outside the fridge, and use the guidelines above to know when to stop using it. Remember, once the pen is kept outside the fridge, the expiration date printed on the pen does not apply anymore.
  • Always inspect your insulin before using it. If you notice any changes in color, clumps, white particles or crystals in the liquid, do not use it. Instead, bring your unopened pen back to the pharmacy where you got it for an exchange.

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  • Q. I recently switched from using syringes to inject insulin to using an insulin pen, and it seems like I need to inject more insulin with the pen to counter the same blood glucose level. The length of the needle seems to be the same, the pen is primed, and yet the pen injection has less of a blood-glucose-lowering effect. What could be going on here?


    A. The insulin contained in vials and pens is identical. So if you’re using your pen correctly, there should be no change in the effectiveness of the insulin on your blood glucose levels. It’s not unusual for people to be educated on how to use an insulin pen and to believe they are injecting with proper technique but to make one or more minor mistakes that affect the amount of insulin being injected. I recommend that you make an appointment with your diabetes educator or health-care provider and have that person observe you injecting a dose of insulin to see what, if anything, might be going wrong.

    Here are a few examples of common errors that can occur when administering insulin with a pen:

    A person may dial in the correct dose, put the needle into the skin correctly, but instead of pushing the button at the end of the pen to inject the insulin, dial the dose back to zero. This would result in no insulin being injected. Once the dose is dialed, the button has to be pushed in all the way — you should hear a series of clicks as you push — and then the pen must be held against the skin, needle inserted, for 6–10 seconds.

    Some people know that they need to push the button to deliver the insulin, but they don’t push it hard enough to inject the entire dose.

    Another common mistake is to fail to leave the needle in place for at least 6 seconds after pushing the button on the pen. If the needle is removed too soon, the full dose of insulin is not administered, and the desired amount of blood-glucose-lowering does not occur. When this happens, you may see or feel a wet area on the skin. The wet substance is insulin that is ending up outside the body instead of under the skin where it should be.

    Some types of insulin need to be gently agitated before injecting. Insulins that are clear in appearance do not require this step. But if you are using NPH insulin or a mixed insulin (a mixture of short-acting and intermediate-acting insulin), the pen or vial needs to be gently rolled back and forth in your hands and inverted up and down a few times to distribute the insulin evenly. Insulin should never be vigorously shaken. It should look cloudy throughout with no floating particles or clumps. If you see particles or something that looks white and powdery, then it is not mixed well, and the dose injected will be inaccurate.

    Priming the pen when you put the needle on is the correct thing to do. However, it is very important not to leave the pen needle on the pen when you are finished. It needs to be removed and discarded. Leaving a pen needle on an insulin pen allows air to enter the pen. Injecting air mixed with insulin won’t physically hurt you, but you will inject less insulin than you think. So remove your pen needle from your insulin pen after each injection. When you put a new needle on to prime the pen, hold the pen upright in the air (with the uncapped needle pointing up), and tap the side of the insulin pen to remove any air pockets that may be in the insulin cartridge.

    It is important to each time you inject. When you repeatedly inject into the same site, a lump of fatty tissue (called lipohypertrophy) may develop. When you inject into a fatty lump, the insulin is not absorbed normally, so you may not receive the full dose.

    You mention needle length. Data have shown that there is no reason to use a needle longer than 4–6 millimeters (mm). When you use a short needle, there is no need for you to pinch your skin up before injecting. You simply inject straight into your skin. However, if you are using an 8-mm pen needle or a 12.7-mm needle (the longest needle available), you need to pinch up some skin at the injection site before inserting the needle. This step lowers the risk of giving yourself an intramuscular (into the muscle) injection instead of subcutaneous (just under the skin) injection. Injecting into a muscle causes the insulin to work much faster.

    Today’s needles are so thin (and therefore painless) that if you aren’t injecting straight in, you could potentially bend the needle. If the needle is bent, you may not get all of the insulin that is being injected.
    Another error that can occur is not removing the inner cap of the insulin pen needle. The pen needle comes with two caps: a larger, outer cap that should be saved for removing the needle from the pen after use, and an inner cap that protects the needle. When you inject you must remove both caps. If only the outer cap is removed, no insulin will be delivered. When recapping a needle for removal from the pen, never recap with the small, inner cap; only use the larger, outer cap to avoid sticking yourself.

    Lastly, the expiration date of the insulin needs to be considered. When kept refrigerated, unused insulin pens are good until the expiration date printed on the pen itself. This may be several years from the date of purchase. However, once you start using a pen, it will expire in 14–42 days, depending on the specific pen you are using. This should be noted in the printed material that comes with your pens, but if you can’t find this information, check with your pharmacist to find out how long your pen is stable once it has been used. Refrigerating a pen that has been used is not recommended and will not extend its shelf life. Insulin that has expired may be less effective (or completely ineffective) and may not lower your blood glucose as desired.

    Want to learn more about injecting insulin? Read “Everything You Ever Wanted to Know About Insulin Injections” and “Ready, Aim, Inject: All About Needles and Syringes.”

    Giving an insulin injection

    To fill a syringe with two types of insulin:

    • Never mix two types of insulin in one syringe unless you are told to do this. You will also be told which insulin to draw up first. Always do it in that order.
    • Your doctor will tell you how much of each insulin you will need. Add these two numbers together. This is the amount of insulin you should have in the syringe before injecting it.
    • Wash your hands with soap and water. Dry them well.
    • Check the insulin bottle label. Make sure it is the right insulin.
    • The insulin should not have any clumps on the sides of the bottle. If it does, throw it out and get another bottle.
    • Intermediate-acting insulin is cloudy, and must be rolled between your hands to mix it. DO NOT shake the bottle. This can make the insulin clump.
    • Clear insulin does not need to be mixed.
    • If the vial has a plastic cover, take it off. Wipe the top of the bottle with an alcohol wipe. Let it dry. DO NOT blow on it.
    • Know the dose of each insulin you are going to use. Take the cap off the needle, being careful not to touch the needle to keep it sterile. Pull back the plunger of the syringe to put as much air in the syringe as the dose of the longer-acting insulin.
    • Put the needle into the rubber top of that insulin bottle. Push the plunger so the air goes into the bottle. Remove the needle from the bottle.
    • Put the air in the short-acting insulin bottle the same way as the previous two steps above.
    • Keep the needle in the short-acting bottle and turn the bottle upside down.
    • With the tip of the needle in the liquid, pull back on the plunger to get the right dose of insulin into the syringe.
    • Check the syringe for air bubbles. If there are bubbles, hold both the bottle and syringe in one hand, and tap the syringe with your other hand. The bubbles will float to the top. Push the bubbles back into the insulin bottle, then pull back to get the right dose.
    • When there are no bubbles, take the syringe out of the bottle. Look at it again to make sure you have the right dose.
    • Put the needle into the rubber top of the longer-acting insulin bottle.
    • Turn the bottle upside down. With the tip of the needle in the liquid, slowly pull back on the plunger to exactly the right dose of long-acting insulin. DO NOT draw extra insulin in the syringe, since you should not push the mixed insulin back into the bottle.
    • Check the syringe for air bubbles. If there are bubbles, hold both the bottle and syringe in one hand, and tap the syringe with your other hand. The bubbles will float to the top. Remove the needle from the bottle before you push out the air.
    • Make sure you have the right total dose of insulin. Put the syringe down carefully so the needle does not touch anything.

    Shake, shake, shake your NPH insulin pen before injecting

    (Reuters Health) – A warning for people who use insulin pens: Not shaking your NPH insulin pen before injecting can result in wide variations in your insulin level and blood sugar control, researchers from Italy report.

    NPH insulin comes as an insoluble mixture of crystals and liquid and must be resuspended before injection.

    Researchers at Perugia University in Italy wanted to know what difference it would make if patients didn’t resuspend their NPH insulin by tipping the insulin pen 20 times before injection – and if they didn’t shake it by tipping it back and forth, whether it would matter how they held the needle during the injection.

    As it turned out, everything mattered.

    One of the researchers, Dr. Geremia B. Bolli, told Reuters Health he was surprised by “the high variability of effects on lowering of blood glucose depending as to whether the NPH pen is properly resuspended or not, and (if it’s not resuspended), even great differences depending on the position of the pen, i.e., horizontal, vertical with tip up or down.”

    “The same NPH appears as a different insulin in each of these conditions,” Bolli said by email.

    Compared with resuspending NPH insulin, not shaking the pen before injecting could result in lower insulin levels in the blood (if you inject with the needle flat or pointing up) or higher insulin levels (if you inject with the needle facing down).

    Your body would also feel the effects of insulin earlier if you injected with the needle down without shaking it first or later if you injected it flat or needle up without shaking it first.

    This could result in your blood sugar rising above desired levels sooner (needle flat or pointed up) or later (needle pointed down) when you don’t resuspend the NPH insulin by shaking the pen first.

    The research team reported in the journal Diabetes Care that insulin levels could vary by as much as 23% and blood sugar control could vary by as much as 62% depending on whether NPH insulin is shaken before injecting, or not.

    “For the users of NPH and also of the pre-mixed insulin (rapid+NPH) it is important to resuspend carefully prior to injection,” Dr. Bolli concluded. “This will reduce variability of NPH effects a lot.”

    Dr. Satoru Yamada from Kitasato Institute Hospital, Tokyo, Japan, who was not involved in this study, told Reuters Health by email that the results show it’s very difficult to have stable efficacy with NPH insulin.

    Yamada advises doctors to select long-acting analogs rather than NPH itself.

    Bolli agrees that it’s great if patients can afford the newer glargine and detemir forms of insulin, but he points out that for many patients, these alternatives are beyond their means. And for these patients, the message is clear: always resuspend your NPH insulin before injecting.

    SOURCE: Diabetes Care, online September 10, 2015.

    Our Standards:The Thomson Reuters Trust Principles.

    Diabetics: Make Sure You Shake Your Insulin Pen Before You Use It!

    (Photo :

    Attention anyone who uses an insulin pen! A study from Italy has found that if you don’t shake your NPH insulin pen well before you inject yourself you may not be getting the right dosage of insulin. Not the pen before injecting results in wide variations in your insulin levels and blood sugar control, the study found.

    NPH (neutral protamine Hagedorn) insulin is an intermediate-acting type of insulin that begins working within 30 minutes and is active for 6 to 24 hours. An NPH insulin pen comes prefilled with an insoluble mixture of crystals and liquid and a user can inject a measured dose with each injection. The pens usually also contain either a solvent or a rapid-acting insulin that takes effect sooner than then NPH insulin. The crystals settle within the pen and must be resuspended before injection. This is usually done by tipping the pen gently back and forth 20 times.

    Researchers at Perugia University in Italy decided to find if it made a difference if patients did not resuspend their NPH insulin, and if they did not resuspend it, whether it would matter how they held the needle while they injected. They found that not shaking the pen and the position in which you hold the pen both make a big difference.


    If the user does not shake the pen properly, the injection may not have the correct mixture of rapid- and intermediate-acting insulin, the study found. Insulin levels could vary by as much as 23% and blood sugar control could vary by as much as 62% depending on whether NPH insulin is shaken before injecting or not, the study reported.

    The mixture also changes depending on whether the injection is done with the needle and pen horizontal or pointing up or down. Not shaking the pen before an injection could result in lower insulin levels in the blood if the needle is horizontal or pointing up or higher insulin levels if the needle is pointing down. These differences could result in blood sugar levels rising sooner or later when you do not resuspend the NPH insulin by shaking the pen first.

    The study was published in the journal Diabetes Care.

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