Controlling Duration of Humalog

Humalog lasts about 5 hours with my son- with the strongest action being between 1-3 hours. The last 2 hours it seems to drop about 60 mg/dl an hour, even with an even arrow on his CGM.

I am trying to get tighter control of his meal boluses, and had the idea to lower his basals after the third hour of humalog in order to make humalog appear to only last 3 hours. I want to do this so I can get his 1 hour peak lower, and not have the tail of his bolus make him low or interfere with the next meal bolus. Of course this means that he will have to eat at the same exact times everyday.

Has anyone ever tried this before? Thoughts?

I’m thinking your son is using an insulin pump. Remember to make any changes to basal rates about two hours before you want to see the effect.

Your tactic sounds reasonable to me. Make notes to help you draw the right conclusions about needed changes as you experiment to hone in on your best plan.

Why do you think he needs to eat on the same schedule each day? If true, I would rate that as a negative and may not survive real life demands. You can set temporary basal rates when needed.

I am glad to hear people are thinking this way. I turned in a request to my pump company that would allow users to link their basal and bolus. It was this EXACT scenario I described to them. I can send you the document if you want to see it. The idea is that the human body doesn’t care if you call insulin “basal” or “bolus”, it treats it the same no matter what the name! I don’t think any pump company allows you to set this up automatically yet.

The best way to make this easy to manage would be to have the meals at the same time, so you could have the pump basal programmed this way. Otherwise, you would need to manually make the change to the basal and just remember to do it! So it depends on how you manage this, whether you would be making the change, or your son. There is risk that you might forget it.

But I like your idea because, it’s the same thing I requested. :slight_smile:

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What I mean is, if I made permanent changes to his basal rates in order to control the tail of his bolus, he would have to eat at the same times everyday. To avoid this, I could give a temp basal starting about 1-2 hours after he eats.

Honestly though, we do end up sticking to the same schedule every day because of school.

I would set a phone alarm to set a temp basal rate and then it would time out at the end of the specified period.

If you find his school schedule supports the meal discipline then your plan should work.

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What you are saying is great! It is absolutely what we, as users, should be able to program.

Here is an excerpt of my request. This sounds like exactly what you are describing.
Insulin pumps treat bolus and basal as two completely distinct and entirely different things. But your body doesn’t really care if insulin was “designated” as bolus or basal. That’s why it’s important to consider everything that is being delivered as part of the same package, regardless of it being basal or bolus. Allowing the PDM to link the two together is the idea behind basal “phasing”.

It would be a tremendous feature to allow a user to program their basal rate to respond to bolus deliveries. Currently, users are limited to modifying their basal rates by either choosing a different basal program, or using a temp basal. But basal programs use preset times, and temp basals only allow one level of increase or decrease, e.g. 50% decrease across the entire time of the temp basal. Temp basals do not allow “phasing”.

Here is a simple example of something a user might like to do. Suppose a person eats their meal at different times, depending on circumstances. No basal program can anticipate this, because the meal time may differ. But a simple dynamic basal phasing program might look something like this:

Example: If I bolus more than 6 units (user can setup their own values), allow me the option to use a dynamic basal response. Keep my basal rate at normal level for the 1st hour after the bolus, than drop it sharply to only 20% after one hour, and have it incrementally rise back to the normal programmed rate over the course of the next 3 hours. So that 4 hours after the bolus, it has returned to its normal program.

These settings would of course be optional, and customizable for the user. The example given is simply an illustration of the idea. It illustrates the adjusted BASAL rate.

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Yes, it’s another way of adjusting the insulin in order to try and match the way your body is actually absorbing the carbs. Unless we eat out at a restaurant or eat pizza, most of the foods that he eats doesn’t need insulin to last 5 hours.
Correction boluses also don’t need to last 5 hours. We need to be able to give more insulin up front and less later.
It would be so much easier if the rapid-acting insulins only lasted 3 hours, and they peaked sooner.

Absolutely! I’ve been asking pharmaceutical companies for that! Still waiting on them to do it!

Share your thoughts about shorter duration with anyone you can. That really would do so much for us all.

Remind me, I’ll send you some thoughts on it. The idea I had to do this was something I called “fragile insulin”. It could only work for a short time before it was unable to bind to a glucose molecule. It would eliminate the insulin tail that causes us problems.

This is what’s behind the appeal of Afrezza. It gets going in a hurry and is virtually gone at about 80 minutes.

I think these bolus/basal trading tactics are creative. I’ve not read about them before today.

I like it, except the big problem is the 4 unit increments (4, 8, 12). I am trying to figure out a way to modify the capsules so I can have smaller increments. The 4 units thing makes it somewhat unusable for a lot of people.

Do you use Afrezza? I find that there is no equivalence between Afrezza units and rapid acting analog insulin units. It’s unfortunate that it labeled that way. You have to do your own experiment and calibrate it to your needs. I wouldn’t want an Afrezza dose increment smaller than the current 4-unit cartridge.

I just recently got some Afrezza, and I have tried it a few times. While I could use it for a meal, the problem is, there is no way I could use it for a small correction. I often do things like 0.10 unit corrections. So Afrezza for me is another tool to use, but not something that can totally eliminate the other rapids.

For the basal phasing thing I mentioned above, I think you mentioned to me that you had to stop using the OmniPod a few years ago. What I pasted above was directly from one of my requests I sent to Insulet.

No pump company does basal phasing yet. We will see if one of them figures out the usefulness…

While I admire the concept of using pump basal rates to control or cut off the rapid acting analog tail, I think not many people will be interested in this concept. If you asked ten insulin pump users to describe what a “super-bolus” is, how many do you think would know? I’m guessing just one or two. I don’t think many have the interest in using and experimenting with advanced pump techniques.

Many people are happy with being able to competently use an insulin to carbohydrate ratio or a correction factor. They would rather devote this energy to their “real life.”

The problems that we have are that my son is going on 10 years old and I hate the idea of him going on a low carb diet. He eats about 50-60 carbs a meal, with a low to moderate amount of fat, and I also try to give him quite a bit of fruit. His spikes are very large 1 hour after meals, raising about 100-200 mg/dl. Even though he is back into range 3-4 hours after a meal, his sugar is in the 220-280 range constantly because he eats every 3-4 hours. Raising the ic ratio keeps this spike down, but then he is low later on. Bolusing 20 minutes before he eats doesn’t really help.

The super bolus is a great option for people that aren’t willing to eat low carb or can’t always eat low glycemic index foods, and I’m sure a lot more people would be interested if they knew it was an option. I wish I knew about it years ago.

This is the first I’ve heard of Afrezza. Our endo told us a long time ago that inhaled insulins weren’t reliable so we’ve never looked into it.

The way I have done if for years, is to over-deliver insulin for the meal, and have a snack available an hour or two later. It is faster to treat a low or impending low than it is to treat a high. You can fix a low in 15 minutes with juice or a cookie. A high can take hours to fix.

With a young one, you can be more aggressive with it when he is at home and you can keep an eye on him. And less aggressive with it when he is at school or not around you. Eventually he will be able to handle the snack need by himself.

I always do it this way. It is much easier to me. Many people talk of an extended bolus. I do it quite the opposite. I view it as an “extended” meal. If dinner is at 7:00pm, then my dessert will be at 8:30pm. And that covers the low, without me ever having been high.


This is kind of what we used to do before the pump. I don’t know, I just feel like we spend so much money to have the pump and CGM that we should be able to tweak things better than we did while on shots. I swear, I think I had better peace of mind before we got the CGM because ignorance of what his sugar was actually doing was bliss lol.

What you is called a “super bolus.” Here is a discussion of the topic by John Walsh of Pumping Insulin fame. It only works with a pump. Basically you set a temporary “lower” basal and add that insulin back into the carb or correction bolus. This in essence stacks the insulin to peak higher initially and then backs off. If you are seeing lows in the time frame of 3-5 hours after the carb bolus you would set a temporary basal for 2-4 hours after the carb bolus of say 50% (you may find a different value works better). You back it off as it can often take an hour for the insulin action to peak.

That being said I find that doing a pre-bolus for meals gives a much better match of my insulin against the glucose load of a meal. It was only after I read Sugar Surfing and got my Dexcom that I realized that I actually need to inject my Humalog 30-45 minutes before eating.

And I know you said you “hate” low carb and you try to lower fat, but that may actually make your situation worse. Fat is actually not bad. A meal that is all carbs can be very spikey and unfortunately (with the possible exception of Afrezza) too fast acting for any modern insulin to deal with. Adding fat and protein to meals can often result in a blunted blood sugar response that is much easier to match with insulin.

Can I ask how long your son has been a diabetic?

Okay, didn’t know you had a CGM too. This makes a huge difference.

Earlier you said pre-bolusing 20 minutes doesn’t make a difference. Well then, the answer to that is to do 30 minutes. If that still doesn’t do the trick, try 40, 45.

You have a CGM, so you can do this very safely. While figuring out his response timing to pre-bolusing, don’t do it with BG below 100-110. This give you some margin to react and head off a hypo.

I have to pre-bolus generally about 30 minutes before I eat to control prandial spikes. This varies depending what’s going on with my BG.

Like everything diabetes, pre-bolusing isn’t formulaic.