In conclusion, nonresuspended NPH insulin before injection may result in an approximately twofold difference in glucodynamic effect (either higher or lower) compared with resuspended NPH insulin, depending on the position
of the pen. For real-life insulin-treated patients with T1DM, and likely T2DM, this may translate to a risk of either hyperglycemia or hypoglycemia. Additional studies are required to establish the comparative within-subject variability
of properly resuspended NPH insulin with that of modern long-acting insulin analogs, such as glargine, detemir, degludec, and the new glargine U300 soon to come (2), to finally answer the longdiscussed question of whether soluble
basal insulins are less variable than insoluble NPH insulin.