Different insulin products have different expiration dates and storage periods, and must be stored according to their respective product instructions. Whether it is unused insulin or insulin products in use, it must be discarded beyond the expiration date or use period and must not be used. Gao Hongjiao, Department of Endocrinology, Zunyi First People’s Hospital Insulin is a protein-based hormone, and its preservation requires strict temperature requirements. The temperature suitable for insulin storage is 2℃-8℃, and unopened insulin can be stored in the refrigerator freezer near the refrigerator door (in this environment, the biological activity of insulin can be maintained for 2 to 3 years). When the temperature is too low, insulin will be denatured by protein coagulation and form crystals, making it ineffective, so insulin should not be placed in an environment below 2°C. Too high temperature will affect the stability and effectiveness of insulin. At high temperatures, insulin may form certain precipitates or filamentous fibers due to denaturation of proteins. Therefore, insulin or insulin injection devices (injection pens) must not be placed in a hot environment, such as on a window sill in direct sunlight or near a computer, television set, or rice cooker that can generate heat. It is necessary for patients to check the appearance and properties of insulin with the naked eye before each use, and to stop using it if abnormal appearance is found. Precautions for insulin use 1. Storage temperature. The insulin being used can be stored at room temperature for 30 days in unopened bottles of insulin and insulin refills (after the injection needle pierces the rubber plug) at general room temperature (about 20°C, not more than 25-°C to 30°C). This time is sufficient for most patients to safely use up a bottle or a whole insulin. Insulin being used is not recommended to be kept refrigerated, this is because the stability of insulin products is better at room temperature and easier to mix, which also makes insulin injections more comfortable, while repeated high and low temperature changes can affect the effectiveness of insulin. 2. Be aware of the adverse effects of low temperature on insulin. Many patients are aware of insulin’s intolerance to high temperature, but they are not familiar with the effects of low temperature on insulin. In fact, insulin cannot withstand low temperatures, and freezing will make insulin denatured and thus ineffective. Even if it is thawed, insulin cannot be used again. Therefore, insulin should never be frozen. Once insulin is found to be frozen, it should be discarded. Patients should be reminded that when storing insulin in the refrigerator, it is best to store it in the refrigerator freezer near the refrigerator door and avoid placing it in the frozen layer. Also try not to put the insulin close to the inner wall of the refrigerator, but close to the door of the refrigerator, because the temperature of the inner wall of some refrigerators is low, which can easily cause the insulin to freeze. When taking out a new insulin from the refrigerator, pay attention to whether there is any icing, so as not to inadvertently use the insulin that has already expired. Also, the temperature of the refrigerator should be checked frequently.3. Preservation in special environments When traveling abroad, insulin should be carried to avoid excessive cold, excessive heat and repeated shocks, and it is best to carry a thermal box with you. When traveling by air, insulin and other hypoglycemic drugs should be packed in the bag carried by the patient, never check in with the baggage, because the checked baggage is easily lost and the temperature of the check-in cabin is too low, which will denature the insulin. The above content is from the WeChat subscription number “Zunyi Diabetes Education Window”. You can join by searching for the micro signal “zytnbw” in the WeChat “Add Friend”, or you can directly “sweep” the above WeChat QR code to join.