Blood sugar level before Bolus/Basal?

Treatment Insulin
1

What should my mothers blood sugar level be before she boluses for meals?

Thank you for all of your responses!

2

Hi,

Typically the bolus for meals is independent from the blood sugar level before eating. Though adjustments / corrections may need to be made for starting high or low sugars.

Let me try to explain.

Fast acting insulin can be used for two purposes:-

  1. Bolus for meals - in this case the amount of insulin should be dosed based on the amount of carbs (and maybe the amount of protein) that will be eaten
  2. Correction dose - this is a dose of fast acting insulin given to correct a high blood sugar.

However, if blood sugar is low before a meal, then less bolus may be given to allow blood sugars to come up a bit.

For example:-

My personal target fasting and before eating blood sugar is in the range of 70 - 90, though preferable in the low 80s (your mother’s targets may be slightly different, depending on what her medical team wants).

My carb:insulin ratio is 10g of carb for 1 unit of insulin.
I also know that 5 g of carbs will increase my blood sugar by 10 points.
I also know that 1 unit of insulin will drop my sugar by about 10 points.
All of these things I know by long trial and error / experimentation / testing.

Situation 1:
Before eating blood sugar is 110 [Correction to get down to 80 would be 110 - 80 = 30/10 = 3 units of fast acting]
I want to eat 30g of carb in my meal [This requires 30/10 = 3 units of fast acting]

Therefore my total dose of fast acting insulin will be 6 units. I also may wait 10 - 15 minutes after injecting before I eat in order to have blood sugars coming down before the impact of the food I ate starts pushing sugars up again.

Situation 2:
Before eating is 86. This is on target. So no correction.
I want to eat 30 g of carb - so I will inject 3 units of fast acting.
I would inject this just before I started eating.

Situation 3:
Before eating is 70. This is a bit lower than I like, though nothing to be too worried about as long as it is not still dropping.
I want to eat 30 g of carb.
I use 10 g of carb to bring my sugar up close to 90 target.
I dose 2 units for the remaining 20 g of carb.
In this case I would inject maybe just as I start eating, as I want sugars to be going up not down.

Of course things are not always this simple in real life, for me time of the day makes a difference (along with the position of the stars, the color I am wearing, and the price of eggs in China…).

I am much more carb sensitive in the morning so I typically eat no / very low carb in the morning, but eat a little more carb at lunch time, and maybe a bit more at dinner. I also do not bolus for dinner carbs (if I eat relatively few 10 - 20 g total), but I always have to bolus for breakfast carbs if I eat more than about 6 g.

… Hope the above could give you an idea of how it can be done and the general approach.

3

I, too, bolus before I eat if my pre-meal BG reading is at least 80 and I bolus based upon the number of carbs in the meal. My BG reacts strongly to carbs, even though my correction factor would lead one to believe I’m fairly insulin sensitive. My insulin to carb ratio (I:C ratio) is 1:3.5 to 1:4 at breakfast, depending upon which fast acting insulin I’m using, Humalog or Apidra. For lunch and dinner my I:C ratio is 1:7 or 1:8. If my pre-meal BG reading is lower than 80, I wait until I finish eating before I bolus, especially if most of the carbs in the meal are low glycemic index foods, like pasta or beans.

My correction factor is 42 on Apidra and 34 on Humalog. (That means that one unit of insulin will drop my BG about that many points.) I target a BG of 100. So if my pre-meal BG was about 130-145, I’d take an extra unit of insulin for correction along with the insulin I inject for food. My insulin pens only allow injections in full unit measurements, so I sometimes have to decide if I want to go for a little more or a little less than calculations would suggest.

4

It varies for each person, but 90-130 is a good starting point. Mine is usually higher most of the time lately.

5

Hi Just lookin,

Thanks for your response and I apologize for the delayed message BUT I got a good laugh out of your quoted quote ( look above).

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6

Awesome, thanks so much for all of your help!

7

Thanks Meeeee for your response! My mother’s BS was 230 before lunch so I had to wait almost 45 minutes to lower it down to a good enough level

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