I've noticed with not only Apidra it depends on my body how long my DIA lasts. At one point years ago I could use R in my pump like the analogs, it worked like Humalog for me at that time, not anymore though. Right now, Apidra works 2 hrs max for me, but month to month it varies for me. There are so many variables with insulin because of the variables of the human body - what holds true to one, doesn't hold for another. The company's estimate on how long any insulin works is an averaged time for one, and just a recommendation really. Novolog has a huge tail for me right now, 6+ hours. YDMV.
