Insulin from various manufacturers is often made available to patients in an emergency and may be different from a patient's usual insulin. After a disaster, patients in the affected area may not have access to refrigeration. According to the product labels from all three U.S. insulin manufacturers, it is recommended that insulin be stored in a refrigerator at approximately 36°F to 46°F. Unopened and stored in this manner, these products maintain potency until the expiration date on the package.
Insulin products contained in vials or cartridges supplied by the manufacturers (opened or unopened) may be left unrefrigerated at a temperature between 59°F and 86°F for up to 28 days and continue to work. However, an insulin product that has been altered for the purpose of dilution or by removal from the manufacturer’s original vial should be discarded within two weeks.
Note: Insulin loses some effectiveness when exposed to extreme temperatures. The longer the exposure to extreme temperatures, the less effective the insulin becomes. This can result in loss of blood glucose control over time. Under emergency conditions, you might still need to use insulin that has been stored above 86°F.
You should try to keep insulin as cool as possible. If you are using ice, avoid freezing the insulin. Do not use insulin that has been frozen. Keep insulin away from direct heat and out of direct sunlight.
When properly stored insulin becomes available again, the insulin vials that have been exposed to these extreme conditions should be discarded and replaced as soon as possible. If patients or healthcare providers have specific questions about the suitability of their insulin, they may call the respective manufacturer at the following numbers:
Lilly: 1-800-545-5979
Sanofi-Aventis: 1-800-633-1610
Novo Nordisk: 1-800-727-6500