Had a light dinner last night--some broiled pork tenderloin and eggplant with 15 carbs of bread crumbs on top. Was 83 and bloused .8, based on BG and I:C ratio, at 6 pm. I ate--even added some sweet tomato butter that I did not include in the bolus calculation.
By 7 pm, my CGM began to alert me to a low and continued until 1:00 am. I drank juice over that time--about 2 cups total that equals about 60 carbs, which would require 3.5 units to cover.
I also had 3 crackers with jam about 8pm, and a small piece of chocolate. Ate more to correct the low than I ate for dinner......
What kept my BG so low, even with all the carbs I took in?
Hi Spock. I had an experience one night where long after I'd eaten or taken any bolus my BG just kept dropping. I just kept treating it with glucose tablets - way beyond my normal amount (I can't remember specifics) and even a snack which I never do, and it just kept going down. It bottomed out at 28 though that took hours and at some point I just disconnected my pump and it finally started going up. Oddly it wasn't high the next morning! I posted on here at the time and finally what I concluded was that I had some kind of absorption problem where the insulin was getting "stored" under my skin and then released later. That was the only thing that made sense. Not fun, I know!
I've experienced symptoms like you describe, an almost overwhelming bias toward hypos. Sometimes I can explain these episodes as delayed hypos after a day of sustained exercise. But sometimes there just appears to be no rational reason for this incessant dive in BGs.
As much as we PWDs like to be consistent with our treatment using the same insulin sensitivity factor (ISF) and insulin to carb ratio (I:C), I think that sometimes our bodies' metabolic needs can temporarily change. I also think that those changes can occasionally be extreme.
I can't guess what happened to you but I have a theory. While our metabolisms generally like to be consistent sometimes they act more like the exception than the rule. Perhaps the liver, which usually secretes a consistent amount of glucose (it also varies according to time of day), may decide to stop putting out its usual glucose flow for a few or even several hours. If my speculation is correct, then the "usual" insulin that we deliver, basal and bolus, will overwhelm the small amount of available glucose and drive us low.
I have an insulin sensitivity factor of 1:50. That is, if I take a correction dose of one unit of insulin, I can usually expect it to subtract 50 points from my current BG. I've read that some PWD here use different ISF's for different times of day. ISF variability within one day doesn't seem that odd to me. What if your ISF can change a lot, like going form 1:50 to 1:100, just every once in a while?
One thing I know for certain is that diabetes and blood glucose management is a dynamic game. We all depend on using the same I:C and ISF because they usually work. Diabetes, however, seems to delight in changing the rules, sometimes drastically. That's why it's essential that we monitor closely and respond appropriately when the rules drastically change.
You may never figure out what metabolically happened last night but I congratulate you for rolling with the punches and giving your body just what it needed when it needed it!
Now you need to remain watchful that perhaps your I:C and ISF may have changed as part of a trend, and last night was just a harbinger of that new trend.
I also have lows and highs that I can't explain, more lows I think although lately more highs. I think for some internal reason, my body wants to run higher or for lows more glucose is needed or as Terry said maybe the liver lowers glycogen levels. I think sometimes activity long before the low can drop me. Usually I get very hungry when a low like that is coming on so I test or sometimes just start eating a snack, or add more food to my meal.