I'm not sure that it really makes a difference, but pump manufacturers recommend using buffered insulin in pumps. One brand of buffered Regular is called Velosulin. Local injections of insulin may cause lipoatrophy orlipohypertrophy. With the purifications of insulin and the use of human insulin, these local complications are very rare nowadays, except among children. For instance, I have not seen them very often among my adult patients, but when I go to the Camp every other kid has some lumps in the fat of their arms.
Duration is listed as approx.
Duration is shown as approx. This type of insulin was developed to allow mixing insulins without the problems associated with mixing the zinc insulins with Regular. The Protamine slows the absorption of the insulin giving the familiar NPH activity curve but does not combine with the R when mixed, leaving the R its fast acting curve. The free zinc will bind Regular insulin and cause a mixed activity curve if L is mixed with R. Duration approx. Same as Monotard save for source.