I have been a type 1 diabetic for 23 years and strangely enough I still don't have any idea how long it takes for my fast acting insulin to kick in. I tested today at lunch and I was at a high of 21.2 mmol/L. I believe that I had breakfast without taking my insulin. After something being like second nature it's funny how you can forget if you actually took it or not. Anyways, I went for a 7.5km run and it took me 41 min. I thought that my blood sugar would be relatively lower but to my surprise it has only gone down to 19.0 mmol/L. This is what made me wonder how long does it take for insulin to kick in? Should I take more? I take Novorapid; 1 unit for each 10g of carbs ingested as well as Lantus before I go to bed. I've looked it up online but of course like everything else the answers vary from one side of the spectrum to the other.
I'm hoping that maybe one of you well educated diabetics or diabetes worker can help me out.
I did take a correction before going for the run and that is why I was wondering how fast it takes to start acting. Sorry if my OP wasn't clear on that and thanks for your reply.
Your insulin may kick in faster or slower at different times of day, too. So the idea is to test it out in yourself. Sometime when your blood sugar is up to 9.9, give yourself one unit of Novorapid, then test at 15 min., then at 20, then at 30. Find out. When it starts lowering your sugar will be the best time to eat. The problem is that if you do this in the morning, you may find that at supper it's different, so choose your tests!
Apidra starts working for me in about 15-20 minutes & lasts about 4.5 hours. Correcting highs takes longer because it seems that insulin resistance kicks in with high BG, or we're on an upward swing & not really correcting enough.
Adrenaline during strenuous exercise can cause highs, usually followed by lows later.
Novolog seems to start in 20 minutes or so for me but doesn't really get cooking for like 1.5-2 hours. I wouldn't worry about pushing your BG up exercising unless you are running really hard, like sprinting. I suspect it would have started to come down later. If I run high, I'll do a correction bolus and go run and don't worry about it too much.
When was the last time you were 378, AR?
Spring break maybe? I don't usually run up that hight but had a weird scene in LA, like the extreme end of a pump, 5 days or something and ran the pump out so I couldn't eat anything at the Entourage cafe...
I'd still run it down though. Exercise always seems to fast track correction boluses for me. I've read the "don't exercise when you're high" stuff but don't buy it. Get it down.
my insulin kicks in real fast...I bolus right before I eat - UNLESS I am dealing with a high bg, then it takes longer to 'kick in'. I don't know why that is but when that happens, I wait till the correction occurs before I do anything else - including eating, exercise, etc.
I don't think you need a new diabetes doctor by the way. We are all so different, the best ones know that you have to learn what works for YOU. Sorry you had high bg like that, I bet my purse that it was a skip of insulin for your bfast and hope you are okay now.
Thank you everyone for your knowledge and advice. I definitely need to sit down with my endo and figure some stuff out. For example I don't know what my ISF is and wasn't even aware that such a factor existed. I am not a perfect diabetic by any means and I really want to take control of this disease so thanks again for all your help.
You might want to get the book Using Insulin by John Walsh, Stephanie. It explains so many of the little details that many doctors either don't know or don't have the time to go over (like ISF)
Your doctor may give you a number or a formula, but really the only way to figure out your ISF is by trial and error since we are all different. When it's moderately high, take one unit of insulin and see how far it brings your blood sugar down in three hours. Do this regularly and write down the results, starting conservative and raising or lowering the number as indicated. Also it may be different for different times of day; mine for example is 30 during the day but 60 at night. (One unit drops me 30 points during the day but 60 points at night).
Well, 21.2 mmol/l translates to 378 mg/dl. In Germany we have the rule to have no sports above 250 mg/dl. For these high numbers you will inject massive amounts of insulin. To combine this with additional physical activity can lead to severe lows. The high glucose can be the sign of having a huge deficit in insulin coverage. In this case the body might have already changed its energy source from carbs to fatty deposits. As a result high levels of ketones from burning the fat might be flooding your blood stream. With ketones it can be really dangerous to get physically more active (risk of DKA). In this situation you will need much more insulin because the insulin sensitivity will be greately reduced. You also need to drink more to flush the ketones out of your system. Another point is that some physical activities might trigger the muscles to release their glucagon stores. This can further increase the blood glucose. In this situation one variable - the insulin - will be enough to control. Inject, test often, drink and bring it down safely.
I do not exercise strenuoulsy over 250. I do what Holger suggests: Drink a lot of water, inject with Apidra once, then closely, for 3 hours;Monitor the blood glucose. I may have to do a correction through the pump about 3 hours later to get it to the 100 -120 range I like in order to eat a meal or snack. I will exercise and correct if under 230 or so, but not strenuously Just light house work or a brief stroll around the block.
re the correction using severe lows business, I use the "exerchart" from "Think Like a Pancreas" as the basis for the correction, taking a %age of the bolus based on duration and intensity of the exercise, usually "moderate" for me. So if I'm at 300 and the pump says say 2.5U, if I were to exercise for 30 minutes at moderate intensity, I'd take .67 of my calculated bolus and then exercise it down. I haven't ever had DKA and sort of think that is more likely to result from prolonged hyperglycemia than an "oops, maybe that was more carbs than I thought..." I also find the fact that I'm engaged in an activity that will push my BG down makes me feel good and all of that but I may be a weirdo about stuff like that. The CGM pic on my page here @ Tu is from the Chicago Marathon, pretty much starting w/ the end of night and showing the boluses during the race.
I have a pic of the "exerchart". I know it's online but haven't been able to find it.