About 2-2.5 hours later, my blood sugar falls into the normal range, or goes low. It doesn't seem to matter whether I eat carbs with protein. My CDE suggested an extended bolus (I'm using the omnipod, just started about a week and a half a go.) I've tried waiting 15-30 minutes before eating--I use humalog--but I still see the spike.
I just can't figure out what to do. If I hold back some insulin for the extended bolus, it seems like it would just make the short-term spike worse. I've tried holding back about 20 percent, for an hour, but it doesn't seem to help. Any tips appreciated.
I can’t speak to the extended bolus example because I’m not a pumper, but I wanted to make a couple observations about the first two examples. In the first one, I’m wondering if you take into account when you compute your correction bolus what your insulin on board is? If not, that would account for going low (assuming your ISF is correct).
In the second example, did you add a correction into your bolus? Since you started out significantly high you would need to either correct first or add it into the bolus.
Actually, perhaps I am dense. I thought an extended bolus was appropriate when you had a blood sugar profile that continued to peak beyond the action profile of the insulin. Perhaps for a mixed carb/fat meal. In your case, I just don’t really see it being appropriate. In the first case, you were high at about 2hrs and then corrected and went low, clearly not a situation for an extended bolus, in fact, you probably would have done better with your bolus and correction all taken before eating. In the second It seems perfect, you return to your starting BS after 1:37 (although I would have added a correction to the bolus too) and you don’t rise further. In the third case, with an extended bolus you seem fine (was that a carb/fat meal?) (but again, no correction).
So, I am confused. If you are having a postprandial high (1-2 hrs) and then a subsequent low (3-4) hrs, then a better matching profile for covering insulin is to stack it earlier, not to extend it.
You’re not at all dense. I had the same understanding of extended or squared boluses as you. They were appropriate for, say, pizza. But I’m almost always eating low-fat, lean-protein meals. Still, my educator said she saw people get good results by extending the delivery, but I’m not seeing it.
Bolusing even sooner than 30 minutes is the only thing that seems to make sense. Most times, I’m going high 180-200, and it’s uncomfortable, but if I wait for 2.5 hours, I’m back in the normal range or low.
I guess I was hoping I could adjust the basal rate or IC ratio, since this is so consistent. But I’m new to pumping, and it wasn’t immediately apparent what I could do.
I was waiting 35 (!) minutes with Humalog. My endo switched me to NovoRapid (same as Novolog) and it seems to help. Now I wait at most 10-15 minutes. Perhaps you should try if your results are better with Novolog or Apidra. People’s experience with the different types of insulin varies a lot. So it’s best to try all three out and see what works for you.
Novolog was definitely faster than Humalog for me!
Other than the first example, I’m not seeing the low. In the second example you’re 25 pts below the pre-meal number in two hours, just about when your humalog is peaking. In the third example you’re only 13 pts higher in about 2.5 hours. In the first example taking a correction bolus less than two hours after your meal bolus explains the drop - you’ve stacked your insulin.
In the last two examples, if you’re still going down into lows 2-2.5 hours after the last reading given (that would be 4-5 hours after the bolus), I would take a look at the basal rate because your insulin has already peaked. Your basal rate may be too high. I think that’s the first place to look. Have you got a copy of “Pumping Insulin” by John Walsh? It explains how to test, adjust and confim your basal rate. After the basal is set, you can play around with the bolus and carb ratios.
As for the extended bolus, like any tool, it has more than one use. Yes, it’s great for meals with extended absorption rates, like pizza and pasta. But when correcting for a high reading it’s also appropriate to use an extended bolus to avoid dropping too fast and suffering a ‘rebound’ affect where your body starts releasing glucogen from your muscles and liver thereby dumping sugar into your blood and raising you BG yet again. Now starts the roller coaster. In fact, I just confirmed this use of the extended bolus with my CDE today.
I was having this when I wasn’t eating mixed meals - when I was eating a majority of carbs with my meal. When I mix it up with fats and protein, I don’t have this issue. Have you tried to do a combo bolus?
At a basal rate of 1.3, I was chasing the insulin in the afternoon and evening. My BG would go low after lunch and before dinner. Now I’m at 1.2 all day. Still, I think that’s what makes the most sense–a basal rate that’s too high, and is taking me down after the meals, after a spike. Just not sure how to avoid the spike. I actually have some novolog, so I’m trying that. And I’ll wait a bit longer before meals, and try to go a little low-carb with the meals until I get this worked out. And thanks, Terry, for the suggestion on the book–I’ll check it out. I have a ton of data because I also use the dexcom CGM, but I can’t easily download it to my Mac. I’m trying to get my Mac to work as a PC so I can track this more easily. I showed the data from my Omnipod (bolus/carbs) but not the lows I’d see on my CGM after the spike. I’m trying to get a better picture together–I could, of course, just write it all down, as I did for the first couple weeks before and a week after I started the pump. I do need to collect data on the carbs I take in for correcting–I’m not tracking that right now.
I’m not sure what basal testing is. My basal rate was set based on the amount of Lantus I’ve been using. Now we’re just dialing it down as I see how things go. I used to see a rise in the morning, a pretty dramatic one, without eating. The pump has greatly minimized that, which is one of the reasons that I’m a big fan of the pump. I definitely recognize that I need to be patient and not stack the insulin–it’s hard, as I was overdoing that on MDI. Bad habit, hard to break, but I’m working on it. My I:C ratio is 5 (there have been a lot of adjustments, it was I:C of 4 in the a.m. with a basal of 1.3 and the rest of the day was a basal of 1.2 and I:C ratio of 5. Now I’m at 1.2 basal rate all day, and using the I:C ratio of 5 all day.) I do use the wizard in the pump, which also tracks IOB. And yes, my TDD is 60-70 units. I use humalog. My educators and doctors say there’s no difference between Humalog and Novolog, but I’m interested to find out for myself. And I think I also just have to realize that refined carbs will hit me faster, even if I wait. I’m so happy with the pump, I just really want to get these spikes down. Thanks again, everybody. Love this place.
That is a great explanation. Did some of that stuff come from the minimed pumper school? Is that training useful? As I understand it, some pumpers have up to 10 basal rates (http://www.insulin-pumpers.org/about.shtml).
Very informative thread. We still have this problem. The reason, I believe, is that her D.I.A. is four and a half to five hours on Novolog. Using Apidra has lowered the spikes. Still go up to 200 for a brief period of time but she does eat a substantial amount of carbs at two of her meals. Apidra helps because, even though her DIA is still four hours with Apidra, there is less of a tail or drop from hours 2.5 to 4. Still drops, but much less than with Novolog. Super bolus sounds like a great idea (haven’t tried it yet; have heard of it). If you are alert and can check at the two hour mark, overbolusing works great. You would analyze and feed the insulin with a few carbs at the two hour mark. This will eliminate the postprandial high; but you cannot forget to check and adjust or you will have a problem. Another thing you could try is to temporarily lower the basal after meals for hours three and four. In our case, can see the results of a basal increase or decrease one hour after making the change; though endo recommends making the basal change two hours before. Superbolus seems more sensible in this instance. Many great ideas on this thread and I will also try some of them. Worried about her going low while at school so have not perfected the postprandials during the school day.
Hi Paul, don’t feel like the lone ranger, this is very typical for type 1 and it takes lots of trials and errors to moderate the post prandial spike. If you are an auto immune caused type 1 remember that most type1’s don’t have pancreatic beta cells that produce insulin, they’ve been destroyed by the immune system. You may already know that the beta cell not only produces insulin but another hormone, amylin. We can’t live without insulin but we can live without amylin. Amylin is an important hormone in that delicate balance of keeping blood sugars normal. Also important in that balancing act is glucagon, a counter regulatory hormone to insulin, which is also produced in another pancreatic cell, some of us type 1’s also can have abnormal activity/production of glucagon, especially if we’ve had diabetes for many years.
The reason I’ve mentioned all this is that understanding this delicate balance helps one in our efforts to normalize Bg. The human body is pretty efficient in normalizing Bg with this system of counter regulatory hormones which are able to deal with an almost infinite variety of factors which influence Bg whether its food, insulin, exercise, time of body clock cycles, infection, stress, and hundreds of others. We can manipulate as many of these factors as we can to try to outguess what the non-diabetic body can do automatically. One of the big factors missing to many type1’s is that hormone amylin, especially for that post prandial spike.
Amylin is not needed for life support like insulin and many doctors write it off, feeling that we can do without it, which we can, but it’s so important in fine tuning that Bg regulation. Much of the post prandial spike is not only the response of the food intake but from the liver “squirting” in glucose from the glucagon/glycogen response as part of the balancing act. That’s one of the roles of amylin, it temporarily slows that liver response after eating.
Symlin is the synthetic version of amylin and is injected preprandial and is very effective for many in moderating that post spike.
It’s not very popular with many Doc’s because it’s another very tricky timing and learning curve on how to use it. It’s relatively new, compared to injected insulin. I’ve found that most endo’s don’t even mention it to patients as an option, I’ve even run across docs who don’t even know what it is. If your endo hasn’t mentioned it to you it might be worth exploring it, there’s also a group here on Tu for Symlin users. Check it out.
Sorry if I’ve rambled about stuff you already know but others who read this might not have heard about Symlin. For me it’s been fantastic as I’ve battled those post spikes for years. It is not a magic bullet by any means and is real tricky to use timing wise, but, it does lower ones insulin requirements and if some of the theories that too much insulin can be part of the diabetic complications keeping our insulin requirements lower may stave off those complications. And if non diabetics have this hormone why should we not have it!
Hi John G,
At first I did have to learn new timing to avoid post prandial hypo’s and yes you have to be aware of your exercise but you can learn how to adjust to that, too. It takes some getting used to but other than the inconvenience of an extra shot in addition to my pump bolus I find no draw backs only benefits. I can sometimes keep my Bg 90-110 after eating and using about 60% less bolus insulin than I used to.
Here’s a enlightening webpage about a CDE who uses Symlin: http://www.diatribe.us/issues/20/thinking-like-a-pancreas.php
Paul, is your basal rate set at the same steady amount all day & night, or does it change over time? I ask because my son’s basal is set to decline in increments of .05 units overnight, and then rise again incrementally in the morning. As an example, between 2:30 a.m. and 5 a.m., he receives 0.10 units/hour, but from 10 a.m. to 12 p.m. he gets 0.25 units per hour. The reason for this is that between his activity patterns and eating patterns, he needs more insulin during the day and much less at night, and taking into account the peak profile of the insulin, I need him to have a little extra that peaks in mid afternoon, or he goes high, and that happens no matter what he eats in terms of carbohydrates. So maybe one thing to ask your diabetes educator about is setting your basal rate in accordance to what you need at different times of day - you may still end up getting the same absolute amount of basal insulin, but might get less at some times and more at others.
Thanks Elizabeth–I started with one basal rate, as a sort of baseline. I’ve only been using the pump for a few weeks. With Lantus, I was seeing rises in the morning without eating. With the pump, the rise in the a.m. is very small. That’s one thing I really like about the pump, it seems to help with the dawn effect. But I do need a bit more insulin in the morning than during the rest of the day, so my basal rate is .1 unit higher from 7 a.m. to 11:30 a.m.
I’m trying to take all this information in–and I’ve ordered the Pumping insulin book. I’m trying to reduce my basal rate and increase my bolus a bit. It’s helping with the spikes, but I’m still going low after about 3 hours.
From your description and some of the comments here, I would definitely focus on getting your basal rates fine-tuned. Not the most fun exercise in the world, since it involves skipping some meals and you have some risk of going low when you discover that some of your basals are too high.
Once you have your basals more established, if you were to see the PP spikes followed by a low like your first example, I would bolus the 10.5u and then do an extended bolus of 2.0u over 2 hours. I do something similar for breakfast when I’m pretty sure my post-breakfast activity is going to be low.
