How to Store and Handle Insulin

Always read the instructions that come with your insulin. Bottles of insulin, either open or unopened, generally last for one month when stored at room temperature (59 to 86°F). A bottle is considered open if its seal has been punctured. If you remove the cap but don't puncture the seal, the bottle is still considered unopened.

If stored in a refrigerator, unopened bottles are good until the expiration date printed on the bottle. O
pened bottles that are stored in a refrigerator should be used within one month of being opened. Many people store their unopened bottles in the refrigerator and keep open bottles at room temperature because they find it uncomfortable to inject cold insulin.

Don't use bottled insulin past the expiration date printed on the label. And no matter what the expiration date is, throw away a bottle one month after you open it. To help you keep track, write the date that you opened the bottle on the bottle's label.

With insulin pens and their cartridges, storage life ranges from seven days to one month. Check the chart below for shelf life details on popular brands.

Insulin cartridges 1.5 mL

Humalog (28 days)
Novolin R (30 days)
Novolin N (7 days)
Novolin 70/30 (7 days)

3 mL

Novolin R (28 days)
Novolin N (14 days)
Novolin 70/30 (10 days)
Novolog (28 days)
Lantus (28 days)
Levemir (42 days)

Prefilled pens Humalog (28 days)
Novolin R (28 days)
Novolin N (14 days)
Novolin 70/30 (10 days)
Novolog (28 days)


There are two ways to tell when insulin is no longer good: poor performance and unusual appearance.

If your blood sugar stays high even though you're following your treatment plan, your insulin may have lost its effectiveness. Poor performance could be due to two things:

  • Your insulin bottle has been open for more than 28 days.

  • You have a lot of punctures in the rubber stopper because you take very small doses of insulin and you're getting close to the end of the bottle.

If your insulin has an unusual appearance, it's probably no longer effective. Here are some warning signs:

  • Your insulin is cloudy when it is supposed to be clear.

  • Your insulin is supposed to be cloudy but it has clumps, even after rolling it between your palms.

  • Your insulin looks stringy.

  • Your insulin has changed in color.

If you think your insulin has gone bad, don't take any chances: throw the bottle away immediately and open a new one.

Smart Tips for Insulin Storage


The BD Diabetes Learning Center describes the causes of diabetes, its symptoms, and diabetes complications such as retinopathy and neuropathy. This site contains detailed information about blood glucose monitoring, insulin injection and safe sharps disposal. Interactive quizzes, educational literature downloads and animated demonstrations help to teach diabetes care skills.

Important Note: The content of this website is not intended to be a substitute for professional medical advice, diagnosis or treatment. Do not disregard your doctor's advice or delay in seeking it because of something you have read in this website.

Unless otherwise noted, BD, BD logo and all other trademarks are property of Becton Dickinson and Company. © 2017 BD