Why do different sources list different onsets, peaks, and durations for insulins?

[fatrabbit]

For example:NPH insulin

my instructor's ppt says onset: 2-4 hrs, peak: 4-10hrs, duration: 10-16hrs

my text book says: onset:1-2hrs, peak: 6-14hrs, duration: 16-24hrs

UCSF website says: onset 1-2hrs, peak: 4-6hrs, durations 12+ hrs

does it have to do with individual patient variation? doses? Sorry if there is an obvious answer to this; we never went too deep into insulins this semester (1st).

[KatieMI, BSN, MSN, RN]

Because they all are based on different studies, which, in turn, were made in different conditions, different populations, humans or animals, with insulin pumps or without, etc. 50 white male Navy SEALs are not likely to show the same equated results as 50 type 2 mostly non- white 2 type diabetics from an inner city hospital. But both results were publushed, and therefore can be used.

The point is, this insulin is not expected to act within 15 min as Humalog, or not have any peak at all as Levemir. It will start within a couple of hours, and work somewhat for a whole day or night. So, it makes no sense to give it before every meal. It can be used as daily base coverage or, using "tail" action, as night time base if given at lunch with dinner at peak time. Everything else is highly variable even for the very same patient who takes it for eons.

[pmabraham, BSN, RN]

I do recommend asking the professor how to handle PowerPoint vs. book variations using the insulin one as an example. In our case (similar situation, but different issue than insulin), the professor shared the book always wins.