candi-girl said:
Thank you, see, I never knew that.
Didn't realise human insulin worked so slow? thought it worked fast like Humalog.
Real human insulin as produced by the body does work fast, It lasts under an hour from the time produced in the pancreas to being totally degraded . It is released on demand.
When you inject insulin as a basal you want it to last longer, otherwise you would have to keep injecting(that is what an insulin pump does) .
It is also difficult to predict how quickly it will be absorbed, and this varies from person to person and site to site, This means that the speed in which the various insulins start to work and the length of time they work for varies betwen people.
Humalin I : the I stands for isophane . It is otherwise called NPH.
The NP standards for neutral protamine.
The H stands for Hagedorn who discovered that adding protomine could make insulin work longer
The protamine was originally obtained from the sperm of river trout (now made in a lab).They had to change the acidity of this protamine to ph7 hence it was neutral protamine
http://en.wikipedia.org/wiki/NPH_insulin
(Humalin I is confusingly called humalin N in the US)