“Highs” after meal causing lows later on

[Nicola M]

I’ve asked this in many places including to my nurses but they’re on annual leave until next week now and I’m at a loss on what to do and it’s driving me a little crazy.

My blood sugar spikes at lunch time without fail every single day, I’m on a hybrid closed loop and it autocorrects for that and I end up dropping low without fail later on and I’m not sure whether it’s because of the corrections kicking in before my actual insulin or what. I’ve tried splitting the lunch dose albeit not for long as my nurse recommended taking my lunch insulin earlier but at this point if I take it any earlier I’ll be going low before I eat. Splitting the dose didn’t help it just made my spike worse (did 60/40). 60% up front and 40% after an hour.

Take today for example, started at 6.9, gave insulin (Lyumjev) at 11:40. Started eating at 12 and was at 4.8. By 12:30 I was beginning to rise and at 13:30 I was 9.1 where my first auto correction kicked in (more came afterwards). My AIT is at 2 hours. It was 2:30 but changing it to 2 hours has made the corrections less aggressive but I do still get some.

I’ve been told all I can change is either my insulin start time but I’m reluctant to give it much earlier as I was going towards low territory today by just doing it 20 minutes earlier or carb ratio but I’m already on an aggressive ratio of 1:8. I don’t want to change what I eat for lunch as I like what I have, it is carb heavy though (2 Sandwiches and crisps). I feel like there has to be something I’m missing. Any ideas?

 

[Chas C]

Bread for me is worst for post meal spikes. Have you tried an extended bolus, its not clear from your post. So % prior to meal (you set the time) then remaining % over time that you preset, rather than splitting bolus. Actually 9.1 post meal is not really high. It may also be that your correction ratio it too high, over correcting and its causing the post meal dives.

Your post also shows that your dropping before lunch, more likely this is caused by pre-lunch basal settings or you could try less time before lunch for first part of bolus. Another option is to miss lunch for few days and look at your basal control around lunchtime, just in case your morning basal is causing the lunchtime lows.