Hi Lizzie,
Many people here pre-inject; it is all about learning how quickly your insulin works in you. If you can break down how many % go per hour then it helps a great deal. Not only does that tell you whether you need a correction shot at hour 2, but it also helps in terms of 'how long before eating can I safely inject?'. Novorapid does seem to take 20 mins to 30 mins to do anything (at least it used to in me) so pre-injecting for that reason alone is good. Obviously do it in a safe place and test lots until you're used to it.
I'd be amazed if Novorapid only lasts 3 hours; in most people, it's still quite fiesty at 4 and is just about gone by 5.
In me, Apidra seems to do 35% of its work in hour 1, 35% in hour 2, then 20% and then the last 10% is gone by hour 4. Now if you can find a food that fits that profile you're quids in
When I first changed to it, I pre-injected one day, ate breakfast and came the closest ever to passing out. The insulin had got a long way ahead of the food. Vision altering, leg shaking, nasty experience.... Go careful if you change as the rules may be different for you.
High fat does indeed slow down the GI. Hence the problem many folks have with pizza; lots of bread which absorbs in a weird way due to the fat and cheese and therefore hangs around far longer than it should.
Gary
