Q. I am on a website where information is exchanged between people with type 1 diabetes. Half the people say that insulin doesn’t need refrigeration after it is opened and half say that it still needs refrigeration. After having diabetes for 42 years, I have never heard that keeping insulin at room temperature is okay. Is it? Doesn’t temperature affect how well the insulin works?
A. The American Diabetes Association recommends that a bottle of insulin can be stored at room temperature (59 to 86 degrees F) for up to one month after it is opened. Storing it in the refrigerator after opening does not make it last longer.
Unopened insulin can be stored at room temperature for one month or in the refrigerator (not in the freezer!) until it reaches its expiration date. Insulin must be protected from extremes of heat or cold, which means not leaving it in the glove box or trunk of the car during the summer.
Mail order delivery can pose problems. One reader had a delivery of insulin sit outside for hours in the winter. The pharmacy told her it should be fine, but it did not control her blood sugar properly. If you get your insulin by mail order, check with the pharmacy to verify that it will not sit in a hot delivery truck or mailbox in warm weather.
