Pre-bolus trick

Saw this some were that was recommended by there endo, what do you think?
If you are in three digit bg reading take the first two #'s and use for wait time after bolusing, example if your bg is 126 wait 12 minutes after bolusing to eat. If you are out of your target range.
I am suspesious but don’t see any harm in trying. Could be anouther small tool in my toolbox, which is almost empty btw.

@T1john, do you use a CGM?

For us, any prebolus needs 45 minutes or more.

Yes, enlite on 530 pump. Surprisingly me sg and bg #'s are normally close. But I use it mainly for trends and low suspends. I finger stick a lot 10+ times a day and am starting on freestyle libre on February 4th. That’s when my free reader from freestyle gets here.

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So what I would sggest, then, is to test how long it takes, for you, for insulin to activate: after a couple of tests, you will quickly recognize the characteristic elbow-down. More than likely, it will be between 30 and 90 minutes. For most of us it is fairly repeatable, about 80+% of the time for us (it takes longer when you are high for us). That will give you an average time to prebolus by if you are in range.

If you are out of range, you do have to add more time to come down. That time will vary depending upon your total injection, therefore it depends upon your meal: more carbs means faster descent. For us, in general it is 5-10 mg/dl over range per 5 extra minutes. So if you are 40 over, you have to add 20-40 minutes on top of the 45 minutes we always prebolus by.


I like to be a generic in the morning’s and test how long to start rise and how high and how long for bolus to act. Unfortunately I don’t log this info so help is minimal, but my biggest improvements have come from tweaking basals.
For side note I started back on pump December 10th with a AIC of 12.8. My estimated AIC IS 5.7 now, on My sugar app. I do log bg’s every 2 hours and all carbs, snacks and boluses. Of course overnight bg’s are taken from pump.


@T1john, what an amazing progress, really fabulous!!! You should be really proud!

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Yea, I am happy but still struggling. A lot of digestion issues causes me no end to grief. That’s why I experiment in morning. Don’t normally eat till afternoon and have really stable bg’s over night of around 90 for most part. Sometimes high when I go to bed and then go low, but suspend kicks in. But I sort of like it when I wake up low gives me opportunity to watch insulin effect over a period of time fasting. Also started/learned to not give over 2 units at any one time/site, use square wave of if need then mid + pump bolus.

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I want to add I couldn’t have done it with out the help from people on this site.


I don’t know what mid + pump bolus means? How long do you square wave it?