High blood sugar at night after going low in the evening



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Happy Saturday!  Today I woke up, looked at my Freestyle Libre sensor, and saw that I had high blood glucose for much of the night.  This is a disappointing way to start my day.  If you monitor your overnight glucose with a Continuous Glucose Monitor like the Freestyle Libre 14 Day system or a Dexcom sensor or other branded CGM, I’m sure you’ve had this happen at least once!!   Maybe achieving in target glucose levels overnight is even a continual struggle for you.

I know exactly what caused it, in this case.  Yesterday, I actually did very well with controlling my blood glucose.  I had a late lunch out and calculated my insulin dose correctly, and stayed within range for most of the day!  However, the late lunch meant that I didn’t eat dinner.  But, at about 8pm, I got hungry and ate some sourdough bread.  I took a 1 unit bolus dose for this.   My body did not react as I expected.  The bread didn’t cause my blood glucose to rise as much as I thought it would have and my glucose level started going low.  I ate food to correct it, but I ate too much, too close to bed time.  I actually got very hungry from the low blood glucose and the final mistake was to 2 pancakes before bed with no additional insulin…

I should be kind on myself and not call it a “mistake.”  Controlling my blood glucose is hard work and I am doing my best with the tools I have.  In the future, I’ll have a Guardian CGM and a Medtronic insulin pump, and probably if this happens, it will wake me up to tell me that I need more insulin, or maybe it will be smart enough to correct it on its own!

Be kind to yourself, this is hard work!

So, instead of feeling bad about last night’s numbers, I will look at my previous days and show you all how good of a job I have been doing!  Last night was the exception… And I will have this experience to learn from, plus better tools in the future!

Here’s what a good day looks like for me! My blood glucose was in range all day!

Side note:  I was particularly unsure of whether to give myself a bit of extra insulin before bed because over the last few days my glucose had been trending lower than usual.  Well, I guess we can say confidently that this low trend is no longer relevant!

At work, we use an agile system called “Scrum” for project management (software development) and we look at “yesterday’s weather” to predict how much work we will be able to achieve.  Likewise, I look at “yesterday’s blood glucose numbers” when trying to make predictions about today’s.  I have variation during my menstrual cycle which is one of the things that makes looking at yesterday’s numbers not always an accurate prediction!!

Be careful about over-compensating in the morning!

When I wake up with high glucose and I see that it was high overnight, I’m very motivated to do some extra insulin to get it in the normal range.  I usually do a half unit of insulin as soon as I wake up to account for the morning rise in blood glucose called “dawn phenomenon.”  Interestingly, I don’t usually have dawn phenomenon when I’ve had high glucose over night.   So I actually got low again in the morning… It’s been a rocky day 🙁

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