High peaks and inexplicable lows

We’ve been having a rough time for the past 1.5 weeks. :frowning: LOTS of inexplicable lows…I’m talking a lot of them. Trying to figure out what’s been going on, but it’s been a frustrating last week or week and a half. Can’t wait until whatever this is…passes. Afraid to start making a lot of changes because, before the last week and a half he was smooth sailing…not flatline like this, but not over 200, 99% of the time, and not under 80 but maybe once or twice.

Here’s a snapshot of the past 24 hours…the last 1.5 week has pretty much looked like this every single day for us. :frowning: The severe drops and spikes upward make treating a frenzy at best…

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Jeez – that IS a challenge. I am assuming you are not overtreating, obviously.

And you have no idea about any change of routine that may be causing this?

Nothing we can explain at all. He’s not really chasing his brothers around any more than he has in previous weeks, and normal amount of playing. We’ve had to cut WAY back on boluses (only have been bolusing for 1/2 his food intake), and we’ve discontinued the temp basal things we had been doing in previous weeks that had been working so great. We are still doing a micro-bolus after his meal when he’s spiking double-arrows up at 150 to stop it from heading up over 250, but this is usually early on and (at least in our minds) shouldn’t account for a post-meal decline into the negative ranges.

Some of these negatives aren’t as “bad” as they look on the CGM…when doing finger sticks, some of them have truly been as low as “LOW” (40’s), but most of them have been 60’s and 50’s (which still isn’t good.)

We take the good with the bad…we know we’re going to have both, thousands of times, in his lifetime.

Two months ago we got puzzled by the same problem. My son had started puberty a couple of months before, and we were starting to get in a groove. But we started getting significant lows appearing practically daily. By significant I mean in the 50s or below (by the CGM though, so not quite as bad for real).

It took us a month to figure it out. In the end, it was us. We had not quite adjusted to the steeper curves we are now dealing with (higher peaks, big insulin corrections, rage boluses etc.), and we tended to wait a little too long before correcting with sugar. It was just an issue of timing on our part, about 10 minutes (depending upon the circumstances really, but often about 10 minutes).

We are still not quite where we want to be, by the way – but we have about halved the more significant lows.

So, what we learned in the process is that sometimes the cause of a problem might be really unexpected :slight_smile: Our universe is significantly more deterministic that yours, so your challenges are greater.

How soon after he’s eating is he hitting the lows?

This is something I’ve been struggling with for nighttime. My son has a hormonal peak at night, pretty much as soon as he falls asleep. Because he doesn’t wind up actually asleep at the same time each night, and because the rise occurs so steeply, it just seems like a poor fit for a basal adjustment preset on the pump.
So we’ve been giving him a bolus when we think he’s fallen asleep. The trouble is that if we wait 15 minutes too long, he’s going to hit 200 somewhere around 10pm no matter what. If we try to correct down, he will go low around 3am to 5am. So the timing on this peak is really critical, and yet also somewhat variable depending on how long it takes for him to drift off.

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It depends on the meal. For some meals the fast and sharp spike incline happens within the first hour, then suddenly, and just as sharply, flies down again…even before the full course of insulin has ran it’s course. This hasn’t been an issue until the past, like I said, week or…now nearly 2 weeks. The “typical trajectory” that his meals usually follow just haven’t been happening lately. Some meals he doesn’t even MOVE (no bump). Other meals he shoots up, then back down again quickly (going low). Other meals he follows “expected” trajectory. Because no one single thing is happening, it’s so hard to pin-point and make any changes…there isn’t really a pattern.

And the sensor is in the same place, Omnipod is in the same rough location? No lumps or bumps near the sites where he’s getting his insulin infused?

And is his TDD unchanged on these crazy roller-coaster days?

I ask because to me when it seems like they spike up super high and then crash, I always wonder if it’s a site absorption issue – like normally a certain amount is active at 15 minutes, but maybe due to the site problem there is no insulin active in the first 15 minutes then all of a sudden it’s all active at once so BG starts crashing down. Sometimes these crashy spiky days sort of settle out on their own, but sometimes they only settle out once we change the site.

Edited to add: Also, on these days we often find the numbers when he’s not eating are still totally steady – what does his BG look like 5 hours after he has eaten on these days?

We he goes low, does he have IOB or does it list negative IOB? (Actually, I’m not sure if you can keep track of that on Omnipod, but that is a useful thing to note). Sometimes DIA can change (i.e. we’ve upped ours from 4 to 5 hours) and sometimes the basal rate can drop inexplicably.

Yes. Yes. No bumps or issues with the site. TDD HAS changed because we’ve been cutting back on bolus amounts and don’t do temp-basal during these times.

Yes. IOB is tracked with the Omnipod and most of the time, he’s still got IOB when he drops low (since over 50% of the time, the “drops” happen even within the first hour of being bolused.

Do either of you use extended bolus for meals?

As of today, we have been “micro-bolusing” after meals when he’s spiking…we’re going to not do that today and see how things work out. I’m not looking forward to the highs we are about to see, but I don’t like the lows…so we have to test things.

We only use extended when he’s eating something like Pizza. None of his regular meals do we use an extended bolus for.

So your TDD was around 6.5 to 8 and now it’s lower than that? What is it now?

The obvious quick and dirty culprits if he’s both spiking up high and then crashing down low are your meal dose and the insulin duration of action. It could be the insulin is working slower than usual, in which case, the same dose but prebolused up front more would help.

Another option, which you may already be doing is to give the same dose of insulin, maybe 5 minutes earlier, but immediately set a zero temp as soon as he eats.

Also, it’s possible all the settings have changed.

To check ISF. Wait for a time he’s a little high (say, 150-180) with no food on board, and give him a little bump down (maybe 0.2?). Does he wind up where his ISF would predict? For instance, if his ISF were 200, and you gave him .2, that should drop him from 180 to 140 mg/dL. If he’s dropping to 100, that means his ISF is too strong and you need to make it a higher number.

To check carbF: Give him something with a handful of carbs (say 4g) when he’s at 100 or 120 and not many other macronturients. For us we like a few saltines. Let him rise. See what he peaks at, typically 60 to 90 minutes later. Let’s say he goes to 180 from 4 grams of carbs, starting at 120. That means each gram of carbs raises his BG (180-100)/4 = 20 mg/dL. Now look at your ISF. If 1 unit of insulin drops him 200 points in BG, then that means each gram of carb, which raises him 20 mg/dL, requires 0.1 units of insulin. So his carbF would be 10 grams carbs to 1 unit insulin.

To check basals: you know the drill on this one but it’s a PITA. Just cobble together an hour here or there when it’s been 4 or 5 hours since his last bolus and see whether his basal rate keeps him steady. Honestly for us basal testing is basically impossible but you can basal test specific very narrow time periods (an hour or two) without too much inconvenience. The plus is you’re only looking at time mostly during the day, and mostly around meal times, so you probably don’t have to do this testing for every time of day – maybe just 6 hours total.

Does he have very scheduled mealtimes? Maybe that would help in debugging – try shifting his meals 1 hour forward or back and see how that changes the dynamics of the post-meal spike. For us our son is on a pretty rigid schedule during the week versus the weekend, which makes it a little easier to debug.

Anyways, good luck. Honestly we’ve had little luck figuring out the cause of these super high spikes and sudden drops. My impression is it’s the site, but I have no way to prove it, and our strategy is to just ride it out and treat lows much more quickly on the downward side (maybe even at 150 or 160 if you are seeing crazy drops that day). But we have plenty of roller coaster days that look JUST LIKE THAT!!

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This is such a scary thought…and frustrating, if true. So much work goes into “getting it just right”.

Have I ever mentioned this disease is frustrating?

Yes, we’ve tested ISF. He has two settings because of how his body reacts during different times. They are currently 10PM - 7AM @ 200, then 7AM - 10PM @ 225.

Here’s his past 30 Days TDD - the “bad days” (the past 1.5 weeks) isn’t much different than the previous 2 weeks of AWESOME BG’s.

He has 3 different CarbF’s based on the time of day. 10PM - 4AM @ 1:23; 4AM - 12PM @ 1:20; 12PM - 5PM @ 1:27 and 5PM - 10PM @ 1:20

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We just did an ISF test on him 4 hours after his breakfast with no IOB… His ISF is set to 225 during the day. His BG was 172 and he received a 0.05 correction (his target is 150). Just 1 hour later his BG was 90 and still heading down. That’s a difference of 82, and dividing by 0.05 units, we get a whopping 1,640 per unit. He wasn’t active during the time (he was playing Minecraft), so maybe his basal was a contributing factor as to why he dropped so quickly. Or maybe his insulin action is longer than 4 hours and the insulin from his meal was still active, but we can’t really test the insulin action, or the ISF for that matter, if he can’t keep from going low over a sufficient period of fasting.


@ErinElizabeth, what’s his basal rate during that time?

It could well be his basal rate is too high, but I agree it’s so tricky to test this. And what I’ve noticed is my kid will go low no matte what r if he goes long enough without eating (usually when we hit 6 or 7 hours). The idea is that basal is designed to produce insulin needed for basic metabolic function – but if you don’t eat for long enough it stands to reason your metabolism might also decrease.

WE just lengthened our DIA From 4 to 5 hours. Since we changed it he hasn’t had crashing lows with negative IOB. He still goes low but it’s when he has positive IOB listed. Also, studies of the drug’s action in the body shows that it is much closer to 6 or even 8 hours of blood sugar lowering effect than the 3 or 4 most people have programmed into their pump. We could never get good results in the past with a longer DIA but now that we’ve switched it seems to be working well. Maybe he just had to grow into the longer DIA?

I think it is tough to test DIA but you could, for instance, give him a small snack that requires a certain amount of insulin (say it’s a 10 gram snack and normally would require 0.5) but then you can deliberately give less, maybe 0.3. With that lower amount, if his carbF isn’t way too strong, he will go high, but hopefully not too high, and when the insulin has finished acting you have a little buffer that he won’t be low, so you can just watch what happens for more than 4 or 5 hours. You can see at what point his blood sugar stops dropping – is it 4 hours? 5? somewhere in between?

Another great way to test DIA is at night if he’s high. If you’ve verified his basal is okay at night, but he happens to be running a bit high at night at a time several hours from his last meal, you can give him a bolus and then see how long his bolus continues lowering blood sugar.

DIA seems like a pretty decent culprit to check. Honestly, you can always just try lengthening it to 5 hours and see what happens. There are theoretical ways to try to deduce what’s going on, but sometimes it’s just worth it to change things and see what happens. With the glucose tabs handy of course.

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@TiaG His current basal rate is .10. He only has a few hours at night when it changes to .15, right around bedtime, but we are thinking of bringing this down to .10 because we are having to give him several unbolused snacks before bed to prevent him from going low. We should get a better handle on his basal; we haven’t spent much time testing it. A lot of what we’ve done so far has been trial and error, making incremental changes and seeing what happens etc. I would love to do more testing even if it means letting him get high enough to provide a buffer, as you suggested, but the trick will be getting comfortable with him being high for a little while in order to do testing.

You could try to have a low carb block of time to try and figure out what kind of basal issues you are dealing with. My boy loves bacon and eggs–so if I have repeated days where I cannot figure out the basal, I will plan a low carb meal during that time to see how his basal behaves.


That is a great trick I never thought of. Nice!

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