Low BS

I’ve been pumping for a month and I’ve had a few lows due to incorrect basal settings and the occasional over bolusing. I had one today, I was at 30 before I really got symptoms of the low, and I ate enough twizzlers, my favorite “treat.” Which is about 10g carbs per stick and I had two because I was low low. Anyways, after the two, 20 minutes later, I was only at 45. So, I repeated and again was barely to 60. Well, at this point, I’m so over this low that I decide that I’m going to have a bowl of cereal, which ended up putting me up in the 390’s. Is it possible to have lows that are harder to treat because of being on the pump? I’ve noticed this in the last few lows that I had. It seems like I am having to basically overtreat them just to get my BS to come up! Any ideas?


One thing to check when you’re low is your remaining “Active Insulin.” This is how much insulin you have left in your body from the last bolus. On my minimed pump (I see you have the Ping, so it might be similar) the way I check this is I pretend to give a bolus and when it gets to the screen where it breaks down carbs, blood sugar, correction, there is an “Active INS” section which tells me approximately how much insulin is still active since the last time I bolused. One thing that might be happening to you is that with a combination of high basals and overbolusing, you have too much Active Insulin in you, which would mean that not only are you low–at 30, 40, even 60 or 70–but that you still have insulin bringing you lower. So even with 3 or 4 twizzlers, if you still have that active insulin, you might only be putting enough sugar in your body to compensate for the remaining insulin, not enough to cover that AND bring you up from 30…which is quite low.

Additionally, this active insulin feature does not account for the active basal insulin you have in you, so if your basal rate is set too high, you not only have that hour’s basal active in you, but you likely have 2-3 hours of slightly excess basal insulin bringing you down. Outside of doing a basal test, what I would suggest for your next low is (1) checking how much active insulin you have left and then (2) putting in enough sugar to cover that PLUS enough to bring you up. The cereal is likely too many carbs (as your BG of 390 showed). I would try some juice next time. I would stick to fast acting sugar like juice or glucose tabs, just while you’re figuring out how to best treat these lows during the confusion of potentially too high basals and overbolusing.


I thought of that too… I checked my IOB (insulin on board) when I couldn’t get higher than 60 and I didn’t have any active… I’m thinking that I’m going to have to do a basal test soon. We, my D-team and I just switched my basal program from the original one that I used when I set up my pump to compensate for afternoon highs and lows when I wake up, my doctor is the one who, based upon my logs, created this program. But I still were having lows on the first program. I dunno. I thought about disconnecting from my pump for a day or so to see, but I don’t think it would be a good plan!

Haha don’t disconnect from the pump! But yeah, a basal test seems like the right thing to do! I had totally forgotten the acronym IOB, thanks for reminding me! Yeah, I really need to do an evening basal test too, I’m STILL honeymooning and my basal rates have been changing weekly for the past 7 months!

yeah not so much here! Yikes I wouldn’t want to have to go through changing it every week! That’s gotta suck! I’m heading to bed… I’ve got the killer residual low BS migraine!

I found my insulin sensitivity on the pump is better than on MDI, and that it has continued to improve since my pump start. I would tend to believe you are seeing the benefit of greater insulin sensitivity which affects just about every pump setting unfortunately. The insulin sensitivity factor or correction factor might be too high, your insulin to carb ratio might be to low, or your basal too high. Also possible is that the duration of action of the insulin is too short leading you and your pump to believe there’s no IOB.

Your endo will definitely know which to adjust first, but it can be a slow process since they don’t like to move quickly and overcompensate.

  • Jeff

When I started pumping my CDE increased my basal to have me not correcting so many highs, then after that she then went further at our next visit, three days later and changed my I:C ratio from 1:12 to 1:9 for breakfast and lunch and dinner is 1:10. My ISF has pretty much been 1:35 for awhile. I use Novolog in my pump and was told it lasts for the majority 4 hours. I’m currently using 1.45u/hr as my basal from 12am to 9pm and then dropping to 1.35u/hr. It took about two weeks for me to persuade them to change that! Too many mornings of waking up in the 50’s. I too am being to think that my ISF isn’t 1:35 but maybe 1:40, would that make that big of a difference?

When I have a low I try to eat something that is fast acting to get my bs up quickly. There are things on the GI list that can get our bs up faster then others. Other then glucose tabs I also eat pretzels and crackers and whatever I can get my hands on.

Hang in there. The pump is a new ball game. One of the big challenges I’ve had is chasing BGs; low or high. There so many factors that impact the BG and it is sometimes a process or elimination to ID the culprit.

The Think Like a Pancreas book helped me out with this. I have to remind myself that any insulin dosage with the fast action, can impact BG from 10 minutes to 4.5 hours after the infusion, basal or bolus.

Sophie made some good points. You may want to try fasting to see if you can nail your basal dosages to get that out of the mix.

Keep us informed and keep it up!