Novorapid, how long to go through?

[ChrisM28]

Hi everyone. Having real issues with very high BS after having been quite stable for a long time. Have used a 1:9 ratio which appears to have gone berserk over the last week so am rethinking everything and testing every 2 hours then trying to analyse the results. BS 14 at 0900 took 5 Novorapid at 1100 down to 7.8 - better. Ate 39 carbs decided to go for 1:8 ratio so 5U + 2 for the high. Will test again in 2 hours. My question is, how much of the 5U from 0900 still had to come through 2 hours later? Does any of this make sense? Am panicking a bit.

 

[urbanracer]

@ChrisM28

Welcome to the forums, - there are too many variables to give you a precise answer, but the profile of your insulin look like this.......



My interpretation of this is that whilst the activity peaks at 2 hrs, the area under the curve is greater between 2 and 5 hrs than it is between 0 to 2 hrs. This would suggest that there's still quite a lot left after the first 2 hrs.

 

[ChrisM28]

Thanks very much

 

[tim2000s]

That's an interesting graph and not one that is distributed by Novo @urbanracer - this is the one from clamp studies where 0.3U/kg was applied and free serum insulin measured after the injection (it's branded Novolog, but is the same thing) @ChrisM28 :

The solid line in Insulin Aspart (NovoRapid/NovoLog) and what you see that is in this dosage, after four hours, most of the insulin has been and gone. Most people's experience is more in line with this graph than the earlier one.

 

[urbanracer]

@tim2000s, sorry but this was my source and I'm aware that it has been referenced on the forums before......
http://www.diabetes-support.org.uk/info/?page_id=408

Curiously, I have now found this on the novonordisk website.....




I assume that this indicates that most of the insulin has been and gone after just 2 hrs ?

 

[tim2000s]

@urbanracer, that's the one I am more familiar with, and the one that has been put into multiple pumps and AP systems.

The key thing that affects duration seems to be dosage per kg of body weight, which seems to indicate the limiting factor is he ability to clear unused insulin out of the system and that there is a maximum rate that this can happen.

At least that's what the clamp studies would suggest.

So the graph you've sourced there from Novo seems to indicate a total dosage of less than 0.1u/kg, based on the studies done at 0.15 and 0.3.

What the studies also suggest is that the entering of DIA in a pump or bolus calculator is incorrect in establishing IOB, and perhaps the use of body weight, with DIA calculated on each dose, would be safer and more realistic.