Insulin storage

Knowing how store insulin properly is very important. If you don't store you insulin correctly, it might not work properly.

On this page, you can find the following information:

Storing insulin in the fridge

Insulin vials, pre-filled pens and cartridges not currently being used should be stored in the refrigerator (at 2–8 degrees) until their date of expiry. Keep them away from freezing coils or the freezer. Do not freeze insulin as this could stop it from working properly.

Storing insulin at room temperature

Store any vials, pre-filled pens or cartridges that you are currently using at room temperature. These must be discarded after 4 weeks of opening. Do not keep insulin in a very hot place (such as in the glovebox of a car) or near strong light or heat, as this could stop it from working properly.

Do not inject cold insulin

Injecting cold insulin may sting and take longer to work. You can warm up insulin as follows:

  • Vial: If you are using a vial, gently roll it between the palms of your hands or move the vial up and down 20 times.
  • Pen: If you are using an insulin pen, turn the pen up and down 20 times before you use it, to mix the insulin well.

Do not microwave insulin to warm it, as this could stop it from working properly.

Check the expiry date

All insulin has an expiry date. Check the expiry date of your insulin and discard any insulin after that date, whether or not it has been kept in the fridge. Once opened, insulin vials, pre-filled pens or cartridges must be discarded 4 weeks after opening.

Travelling with insulin

When travelling, keep your insulin in a cool place. You should store your insulin in an insulated bag or thermos flask to protect it from extreme temperatures.

If you are travelling by plane, keep insulin and all essential supplies in your hand luggage. It should not be in extreme temperatures, including the baggage compartment of a plane where it can freeze.

Learn more

Insulin topics


  1. Practical aspects of insulin therapy Research Review, 2020
Credits: Sandra Ponen, Pharmacist. Reviewed By: Angela Lambie, Pharmacist, Auckland Last reviewed: 17 Dec 2020