A nurse is preparing to administer 30 units of NPH and 10 units of regular insulin to a client. Which of the following actions should the nurse take?

A. Keep insulins stored in the refrigerator: Insulin should be stored in the refrigerator until it is opened. However, once it is open, it can be stored at room temperature for up to 28 days, depending on the manufacturer’s recommendations. It does not require refrigeration for daily use. B. Inject air into the regular insulin first: When mixing insulins, the nurse should inject air into the NPH insulin (cloudy) first, not the regular insulin (clear). This prevents contamination of the regular insulin vial with the NPH insulin. C. Aspirate NPH insulin first: After injecting the correct amount of air into the vial, the nurse should draw up the clear insulin (regular) first, followed by the cloudy insulin (NPH) to prevent contamination. D. Roll the cloudy insulin between the hands several times: NPH insulin is cloudy and needs to be gently rolled between the hands to mix the insulin properly. Shaking the vial can cause air bubbles or break down the insulin.