When giving an insulin injection, how long should you leave the needle in after inserting it? Is there any advantage to waiting before removing it?

That is a really great question! As needles get tinier and tinier, the time it takes for all of the insulin to get through takes longer too. After fully pushing the plunger down, Lilly recommends five seconds; Novo recommends six seconds. This is because it may take that long for all of the insulin to go through the tiny opening in the needle or pen needle. The more units you take at once, the longer it will take to get through. If you don’t believe me, try an experiment in the air. Draw up some insulin or dose an insulin pen, inject it into the air and watch how many drops still come out after you have pushed the plunger all the way down.

JTL