Studies have shown that EpiPens retain the majority of their effectiveness over time. For example, many EpiPens that are two or three years old still retain about 90% of their effectiveness. If you need to (for example, if your child is having an anaphylactic reaction and you only have expired EpiPens), using an expired EpiPen is a much better option than doing nothing.
For more information on EpiPens and storage recommendations, you can consult the website of the National Agency for the Safety of Medicines and Health Products (ANSM).
