I agree that it seems to take a very long time for my fast acting insulin to "kick in" lol I get these awful headaches when I eat-- I give myself my injection before my meals like I was told but it seems that it takes forever for my sugar to come down.. and I am being very careful with what I am eating-- it is almost as if I want to say "skip it" and just eat the "bad"stuff anyways... I have also been experiencing some serious highs and then of course the wonderful lows. Been kinda a roller coaster this last week. I am not sick.. I have been eating well.. so I assume it is either my work schedule catching up with me OR my sliding scale needs to be changed!