How should insulin be stored to maintain its efficacy?

Insulin should be stored in the refrigerator to maintain its efficacy. Keeping insulin refrigerated helps preserve its potency by preventing degradation and ensuring that the active ingredient remains stable. Temperatures that are too warm can cause the insulin to break down and lose its effectiveness, which is why refrigeration is recommended.

However, it's worth noting that once opened, some types of insulin can be stored at room temperature for a limited time, typically up to 28 days, but this is not the ideal storage method for unopened vials or pens. Storing insulin in the freezer is harmful, as freezing damages the insulin, rendering it unusable. Additionally, placing it on a shelf at room temperature without ensuring it stays within the specified temperature range can also lead to a loss of potency, particularly if it exceeds 86°F (30°C). Thus, the best practice is to keep insulin refrigerated until it is ready to be used.