Ambulatory Care Nurse – Board Certified (AMB-BC) Practice Test

Which statement about NPH insulin is true?

It is clear It lasts 24 hours It is cloudy It has no peak

Correct Answer:

It is cloudy

Explanation:

NPH insulin is cloudy because it is prepared as a suspension with protamine, making it an intermediate-acting insulin. The cloudy appearance comes from the suspended particles and you typically roll or gently invert the vial to resuspend before dosing. This suspension-based, intermediate action contrasts with clear, rapid-acting insulins that are solutions. While NPH does provide longer-lasting coverage and has a peak several hours after injection (unlike long-acting analogs that aim for no pronounced peak), it is not guaranteed to last exactly 24 hours in every patient and it is not clear. Therefore, the true statement is that it is cloudy. The other options—being clear, lasting a full 24 hours, or having no peak—do not fit NPH’s characteristics.

Access more questions from this quiz

Continue to Ambulatory Care Nurse – Board Certified (AMB-BC) Practice Test for more practice questions and the full quiz experience.

Access More Questions