Insulin comes in different containers. While most diabetes patients now use insulin pens or even insulin pumps, some are still using the old-fashion way.
In that case, insulin is delivered in 10ml or 30ml vials (small glass bottles) and needs to be drawn out with the syringe that will be used for the injection. That technical manipulation may be impossible or complicated for some patients, which raises the question of prefilling the syringes in advance.
Can you prefill insulin syringes? Are prefilled syringes safe to use? How to store them properly?
Related article: How to Mix Two Insulins in the Same Syringe?
Why prefilling insulin syringes?
There are various situations and medical settings in which prefilling insulin syringes may be recommended in the patient’s interest.
While we have not found any specific guidelines from the United States health authorities, the UK’s Royal College of Nursing recognizes and supports the practice of prefilling insulin syringes “for a small minority of patients who are unable to use an insulin pen and want to remain independent”.
In the USA, prefilling syringes with insulin is a relatively common practice among diabetes nurses and healthcare providers. It can work very well for some patients who demand greater independence and increased flexibility over mealtimes.
Related article: Does Insulin Really Need to Be Refrigerated?
Cases where preloading insulin syringes may be useful
There are many cases where the patient, either hosted in a healthcare facility or living in his own house, cannot fill the syringes himself. Even though the number of people who are affected is quite small, situations are numerous. For example a blind patient, a patient with chronic dexterity issues, a patient with broken harm or wrist, or someone with mental health issues, etc.
In these particular cases, it’s often simpler and safer to have a nurse, a friend, or a family member prefilling the insulin syringes with the exact prescribed units of insulin every few days, so the patient only has to proceed to the injection when he or she is alone.
Another common scenario is for at-home patients who are perfectly capable of using insulin syringes but may want to prepare their doses in advance for matters of self-organization.
While nurses and diabetes patients can prefill insulin syringes in advance, there are some safety precautions to consider first.
Related article: How to Read Insulin Syringes and Get The Right Dose?
Are prefilled insulin syringes safe to use?
Most insulins, including Lantus, NovoRapid, Humalog, Levemir, Humulin, and others, are biologic products. They are complex drugs made from living sources. As such, insulin is unstable, sensitive to temperature and light, and can easily get contaminated and go bad.
The nature of insulin and its rigorous storage requirements impose some safety precautions to be taken before prefilling syringes for yourself, a patient, a friend, or a family member.
Do not prefill for more than a few days
For safety reasons and to limit the risks of contamination, it's good practice not to prefill insulin syringes for more than a few days.
There are no official recommendations as to how many days you can keep an insulin syringe, but it’s safer not to prepare too many syringes in advance. Besides, your dosage might change unexpectedly.
Related article: How Long Do Insulin Vials Last and How Many do You Need Per Month?
Store prefilled insulin syringes in the fridge
Insulin is highly sensitive to temperature and temperature changes. To limit the risks of insulin preloaded syringes going bad, always keep them in the refrigerator.
Remember that unopened insulin must be stored in the fridge until its expiration date, while open insulin is only good for about a month whether stored in the fridge or not.
The insulin you've used to prefill your syringe has been opened and has spent some time out of the fridge. It's only safe to use within the next 30 days at the most.
You can keep prefilled insulin syringes out of the fridge at room temperature. But if you’re at home, it’s even safer to store them in your fridge.
Find out more about 4AllFamily's insulin coolers to keep your insulin refrigerated while traveling!
Store different insulin doses separately
Your patient (if you're a diabetes nurse) or yourself (if you're a diabetes patient) may be prescribed more than one shot of insulin a day, or even different types of insulin during the day. If the morning dose is different from the evening dose, for example, make sure there's no possible confusion.
The preloaded syringes for the different shots of the day must be stored separately and clearly identifiable. Labeling them seems like the safest solution.
Related article: How to Calculate Your Insulin Dose Correctly?
Store the syringe with the needle pointing up
Storing the syringe with the needle pointing up will prevent the insulin from blocking the needle opening. Always keep the needle cap on to prevent bacterial contamination from the outside environment.
Wait for 10 minutes before injecting
While it's not dangerous, injecting cold insulin can be painful or cause discomfort. If you've stored your preloaded syringes in the refrigerator, allow the syringe to warm up for 5 to 10 minutes at room temperature before using it. You can also warm it gently by rolling it between your hands.
Related article: 10 Tips That Work to Inject Insulin Without Pain!
How long can you leave insulin in a syringe?
There’s no official rule as to how long you can leave insulin in a syringe. However, once you've opened an insulin vial to prefill your syringes, the insulin must be used within 30 days maximum. During that time, you can keep the preloaded insulin syringes at room temperature (below 80°F / 26°C), but it’s even safer to store them in the fridge.
Common advice on prefilling insulin syringes is that you should not preload syringes more than a few days in advance.
What are your experiences with prefilled insulin syringes?