How Long Does Insulin Last in an Insulin Pump? Here’s the Guide

Posted August 17, 2020 by Michael Chamberlain - See Editorial Guidelines

Using an insulin pump takes some getting used to. From the various settings, features, and rules to follow, there are always some questions users have about using insulin pumps.

One common question many have with insulin pumps is how long does insulin last in an insulin pump. So, this article will offer some guidance on how long insulin lasts in a pump, and if insulin can go bad in an insulin pump? If so, then when?

So, first, let’s give you the quick answer, then we’ll get into some of the details and instructions.

How Long Does Insulin Last in an Insulin Pump? Insulin lasts about 28-30 days after it is opened and not refrigerated. Insulin pumps generally need to be changed every 2-3 days. So, the insulin you use to fill the reservoir in the pump must at least be on day 25 or 26 since you’ve opened the vial. Patients are recommended not to use insulin beyond the expiration date on the container.

Now that’s the short and quick answer, but other questions always arise from that concerning the various nuances for insulin when it’s in the pump. So, let’s run through those next.

How Long Does Insulin Last in a Pump?

How Long Does Insulin Last in an Insulin Pump

There are two ways most insulin users choose to get insulin into an insulin pump.

Some use the prefilled insulin cartridges that are available through prescription or via PAPs, whereas some draw insulin from a vial straight into the insulin pump reservoir.

So, how long insulin lasts in a pump directly comes from how long insulin lasts in vials and pre-filled cartridges.  

Generally, insulin pump infusion sets will only last 2-3 days. So, insulin is often required to be changed every time you change the infusion set. Therefore, if the insulin vial you have been using has been open for more than 28 days, it is recommended that you do not use that vial to refill the pump reservoir.

Once the insulin pump reservoir starts to run low on insulin, a warning sound is given. This will alert you to refill the insulin reservoir or change the infusion set soon.

So, whether you’re planning to refill using a vial or a prefilled insulin cartridge, then how long the insulin lasts comes from different factors.

These factors are influenced by the storage and temperature conditions that the insulin was kept in before being used in the insulin pump reservoir.

How Long Does Insulin Last in an Insulin Pump When Unopened Insulin Is Used

In general, when unopened, both prefilled insulin cartridge and vials can last for approximately one year from the day of purchase as long as it is refrigerated. It is recommended to keep unopened insulin refrigerated between 36° to 46°F.

Keeping insulin within this temperature before they’re opened and put into an insulin pump is important to ensure the insulin retains all the quality elements it needs to operate effectively.

When an insulin pump is refilled – just after opening, the insulin that goes into the pump can last 28-30 days.

In general, insulin begins to breakdown after the expiration date. But when insulin is exposed to unsuitable temperatures it can breakdown faster, thereby shortening its lifespan.

When we say, “breaking down,” this generally means that the insulin will lose its potency and effectiveness.

This mainly happens because as with many liquids, when insulin is exposed to extreme cold or warm temperatures, bacteria begin to grow, reducing the effectiveness of the insulin in terms of strength, potency, and efficacy.

How Long Does Insulin Last in an Insulin Pump When Opened/In-Use Insulin Is Used

If one uses open vials to draw insulin and refill an insulin pump, it can be a bit riskier. This is because once open, or when in use, insulin lasts for 28 days, after which it should be discarded.

how long does insulin last in an insulin pump

Unlike unopened insulin, which needs to be refrigerated, opened insulin can be kept in controlled room temperatures or refrigerated.

But regardless of whether they’re stored at the right temperature, they have to be discarded after 28 days.

So, to know how long insulin will last in an insulin pump, it’s always recommended to record the date of when the insulin is opened. This will make sure that you’re not refilling an insulin pump with insulin that has passed these 28 days of the lasting period.

If you’re refilling with opened insulin that’s reaching the last few days of use, then the insulin that’s refilled in the pump may not last for long enough.

This is also one of the reasons why many users prefer using prefilled insulin cartridges. Rather than having to manually draw from vials and worry about how many days it’s been since opening the vial, patients can simply look at the date on the prefilled cartridge.

If this seems like an easier method for you, then for your fast-acting insulin, you can explore the Novolog Flexpen option and potentially obtain it through our PAP for diabetes option for just $50 a month via Prescription Hope.

An open insulin vial or pen can be kept at room temperature between 59 and 86 degrees Fahrenheit to prevent it from going bad sooner than the 28-30 day period.

Tips to Help Insulin Last Longer in an Insulin Pump

Never keep insulin pumps in hot places when you detach them. This will expose them to overly warm temperatures, which may break the insulin and reduce its longevity.

While traveling, it’s again important to make sure insulin pumps, prefilled insulin cartridges, or insulin vials used to refill insulin pumps are kept in a cooler to prevent the insulin from getting too warm. However, make sure the insulin is not in direct contact with ice packs while in the cooler. You do not want insulin to freeze.

Preventing the insulin in your insulin pump from being exposed to extreme temperatures will allow the insulin to last the full length of time you have the insulin pump on.

If using an insulin pump is not for you, then read our guide on everything you should know about injecting insulin!

To Close

We’re always keen that you get the most out of your meds, and the most for your money. So, we hope this has provided you with some guidance on the question of how long does insulin last in an insulin pump.

This article is not intended to be a complete medical guide. We would, of course, always recommend consulting your doctor about the best way to use and operate your drugs and equipment effectively.

If you’re having trouble affording any of your medications, then Prescription Hope may be able to help. Enroll with us and see if you qualify to pay only $50 a month for each of your medications.