A nurse is teaching a client who has a new prescription for NPH insulin. Which of the following instructions should the nurse include?

A. "Discard the medication if it is cloudy": NPH insulin is naturally cloudy, and this is normal. It should not be discarded just because it appears cloudy. It should not be used if there are clumps or particles, the insulin should not be used. B. "Take this medication 15 minutes before meals": NPH insulin is an intermediate-acting insulin. NPH insulin has an onset of 1–2 hours and a peak at 4–12 hours, so it is not timed specifically 15 minutes before meals like rapid-acting insulins. C. "Briskly shake the medication before filling the syringe": NPH insulin should not be shaken briskly because it is a suspension and shaking can cause bubbles or foam. The insulin should be gently rolled between the palms to mix it properly before drawing it into the syringe. D. "Eat a snack 8 hours after taking this medication": NPH insulin has an action peak of 4 to 12 hours after administration, which can increase the risk of hypoglycemia during this time. The client should be cautious of hypoglycemia and may need to eat a snack 8 hours after taking the medication.