How should unopened vials of Humulin NPH insulin be stored according to nursing instructions?

Unopened vials of Humulin NPH insulin should be refrigerated to maintain their potency and effectiveness. Insulin is a sensitive hormone, and exposure to high temperatures or freezing conditions can compromise its integrity, leading to a less effective medication.

Refrigeration slows down the degradation processes that can occur at higher temperatures while ensuring that the insulin remains stable for use when needed. It is important to avoid freezing as it can cause the insulin to become unusable. Therefore, proper storage in the refrigerator is crucial for preserving the quality of the unopened vials until they are ready to be used.

Storing insulin in a dark, dry place may be applicable once the insulin has been opened and is in use, but it does not pertain to unopened vials, making refrigeration the most appropriate method in this context.