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sweetlife

I am little confuse on Insulin to carb ratio

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Sorry for opening another thread on I:C,

formula for rapid acting insulin is

1800 devided by TDD

here TDD means in my case Novorapid+Lantus

OR

Only Novorapid?

two different methods I read on net in which one says total daily dose of insulin and another mentions humalog or novolog means only bolus shots,me confuse on this.

rt now I am calculating TDD as novorapid+Lantus units.

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I am probably wrong, but it doesn't make sense to count lantus since thats long lasting and you take the same amount every day, right? It probably just counts rapid insulin, since I only use I:C ratio for rapids.

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I don't know anything about the details of these formulas. But, TDD means total daily dose of basal and bolus.

 

I'm not sure you'll get anywhere at with just a number and TDD for developing an I:C ratio (that's what you want is it?) For a start it misses out a vital variable - carbs.

 

Off the top of my head a half-useful way to do it would be to guestimate the number of grams of carbs being consumed daily and divide by current total bolus. So, as an example it might come out to something like 12, meaning 12 grams of carbs to 1 unit insulin. Probably put it up a little to make the likelihood of hypo less. This should give you something rough to start from. From there the only way is to test and observe and modify accordingly. It's an ongoing process.

 

There may be other ways to "calculate it". But once you get in the ballpark, it's going to be trial and error.

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Subby and Pshycho

This I need to use bolus calculator which m already using with TDD as total dose incl Basal units for my daughter,this query would never imerge untill I saw some sites which tells that only rapid action insulin's total dose should be counted where they wrote humalog or novolog hence came this confusion.

I too feel that TDD means Total Daily(bolus+basal)dose.

for your info her I:C is 7.5.

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This method IMO should only be used for estimating initial doses. It's an average value, and most of our optimal numbers will be slightly different. I find my I:C's by eating the same meal for a week or two then titrating (making adjustments) my dose until I find a value that works.

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I'm still getting my settings set with CDE's help and he used the formula to get a starting point to program into my pump. And we've discovered for me that just as I need different basal rates at different times of the day, I also need different IC ratios. I just began testing before a meal and two hours after a meal, to see which IC's need to change.

 

Sometimes it comes down to trial and error. Just keep good records.

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Little offtopic related to posted subject but someone mentioned a formula like below for rapid acting shot calculation,no idea how this work out.

BS reading -(minus)100=X

now X devided by 20=Y

Y is the bolus shot.

Funny formula,any idea or any of you ever heard of it?This method has absolute no relations with any ratio,just a rough labourman's calculation it looks like!

------just posted this for discussion,above has no scientific base--------

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Sweetlife,

 

BS reading -(minus)100=X

now X devided by 20=Y

Y is the bolus shot.

 

That is someone personal formula for what their body needs, but what we all need is different. It reads like this 100 is the goal blood sugar (this can be set to whatever you think is best) the divided by 20 is how much someone's blood sugar goes down for each unit of insulin. So this persons blood sugar goes down 20mg/dl for every one unit. This formula is would be different for everyone. For example for me I have it like this.

 

BS reading -(minus)80=X

now X devided by 25=Y

Y is the bolus shot.

 

But something for your 11 year old daughter would be really different. Overall though it is a great way to figure out how much insulin you need to take for a high blood sugar once you know your ratio.

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