Random low events

First post. Appreciate any insights.

Im a 33 year old male, dx with antibody neg Type 1 at 31. Been managing with basal-bolus insulins. Occasionally, I’ve had spurious rapid low events in evening… 3 hours after mealtime insulin and no more than 20 mins after long acting insulin… Took mealtime insulin around 530pm, blood sugar was 108 3 hours later at 830pm when I took my normal lantus in the evening. Just 20 mins later at 850pm I felt low and my blood sugar 35 (!)… my CGM didn’t even pick up this rapid drop given delay between blood and sensor. This has happened a couple times before but is very rare and completed unexpected as sugars were fine after expected peak effect time of rapid insulin given at 530pm and long acting shouldn’t drop sugars like that and it was only 15 mins after delivery.

Anyone else experience events like this? I cannot figure out why they occur. Even if I accidentally took mealtime bolus insulin instead of long acting, it shouldn’t take effect that quickly.

Any insights welcome. Thank you and happy to be a part of this community and life long journey.

That will be a puzzle to figure out. When you get a 35 on the CGM, I suggest that u take a finger stick test. Sometimes the CGM is off. Did u feel any symptoms?

CGM showed 100 but I felt low (panicked, sweaty, lightheaded, heart racing, etc) and finger stick was 35, so I know it was a legitimate low… I just cant understand WHY it occurred. Especially 3 hours after mealtime bolus and only 15 mins after basal insulin administration… so essentially I had a rapid onset low with no explicable reason.

Were you exercising earlier? What did you eat? was it low carb, low fat or different from what you usually eat.
My bolus for mealtime does tends to continue to drop my sugar between 2-4 hour as well giving me lower sugars. I am on the pump. What I did was decrease the insulin to carb ratio from 1 to 8 to 1 to 9 then 1 to 10. That stopped the lows but gave me somewhat higher bg. Then I had to adjust the basal during that time as well. It really is trial and error. This was relative to evening and afternoon meals. Breakfast was 1 to 8 did not change.
Call you diabetic team to help you adjust. 35 is scary low It needs to be dealt with asap Check your sugars to see if you are going low on other days but not seeing it thru alarms( signals and symptoms)
Best of luck, Others with more in
sight will pop in soon, Call ur doc.

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Appreciate your advice Typ1! I exercise 4-6x/week but surprisingly this was one of my days off. I have found that even though most days I exercise in the morning, I still tend to be less sensitive to insulin for breakfast and lunch and that I am much more sensitive to insulin (and have lower BGs) around dinner time. By most standards I am probably on a somewhat lower carb diet (I eat 20-30g carbs for breakfast and ~40-80g carbs for lunch/dinner). The couple of other times I had random lows was also in the evening and again, randomly like 3 hours after a meal when my 2 hour post meal BGs were in 90-100 range and then again had sudden drop to 50-60 range without explanation… In addition I am just home relaxing, not exercising, and in those situations was not drinking alcohol either so it’s just so bizarre to me.

Appreciate you!

The simple answer to your hypo question is that you had too much insulin in your system and that drove your glucose down to 35. The more complicated question is whether that was due to an overly aggressive meal dose for dinner. Perhaps your insulin to carbohydrate ratio was too strong and caused an insulin overdose.

Or, your long acting dose, your basal insulin, is too strong. You will need to do some personal experimentation to figure out what factors are important for your particular metabolism. I recommend that you you keep a log of insulin doses, meals consumed, and exercise and stress events. Timing of each of these factors is important as well.

You don’t have to do this forever, just long enough to sort out what your particular solution will be. You can talk to your doctor about this and perhaps get some helpful suggestions. Just be aware that the doctor’s iteration rate for solution candidates will be much smaller than yours.

This problem solving skill, however, is critical to success. You only see your doctor every few months yet you are faced with diabetes treatment decisions every day, often several times per day. Mastering this skill is golden and will reward you time and again going forward. I highly encourage investment in this practice!


What is your exercise intensity and duration?

Basically I alternate days with either A) 15 mins high intensity (15-20 mins burpees/mountain climbers, rower, or 2 mile sprint) + 30 mins free weights or B) 30-45 mins cardio (usually exercise bike) + 30 mins free weights.

I can see the immediate effects of different types zones of exercises (anaerobic vs aerobic) on my BGs depending on how much is utilizing glycolytic pathways vs fat oxidation… but I did not exercise on the day I had the random abrupt low event 3.5 hours after my mealtime insulin.