Extended bolus

Hello everybody,

I was wondering if anybody can share with me how they use the extended bolus feature. I dont really use it that much, but when I do it does not work very well for me. Do you guys have a formula on how much to deliver right away and how much to leave for later? how long do you wait for the rest of the bolus? Any comments will be greatly appreciated.


Certainly a legit question. I don’t use it a lot, but find it very useful if I am eating steak or roast beef. For me, I’ve always gone low quickly, then a few hours later, gone really high. I take 50% right away if Im eating something like potatoes and starchy vegi with it, like corn, then delay the other for 3 hours. Its really a trial and error thing, but it works really well for me with those two things. Don’t have problems with other meats. Baked beans is the other thing that I need to delay - similar thing happens.

I use it for maybe 50% of meals. My wife calculates both carbohydrate and, very approximately, protein. If protein is significant she calculates a total amount including allowance for the protein (very approximately) and then has me do the protein part as an extended bolus over 2 hours.

Normally this works out to 80% or 85% of the bolus delivered immediately, with the rest over 2 hours.

If we don't do this high protein meals will invariably send my blood sugar up after a few hours.

If I'm getting a lot of exercise we skip the protein calculation; the protein is a useful slow release carbohydrate that offsets the exercise.

John Bowler

It's best use is for high fat meals. Fat causes te carbs you eat to be absorbed slowly or even delayed in absorption. So by giving a little insulin now to handle the first spike from eating, then more later to handle the second spike from the result of the fat's actions it will make your BG levels more level over time.

In addition to high-fat, high carb meals (eg, pizza), I use an extended bolus in cases where my BG is low but I'm about to eat a regular meal. I take a low percentage immediately and extend the bolus to deliver the rest in an hour. That way I don't get too much insulin acting before the meal has had a chance to bring my BG back to normal.

I use it with the "4 P's"

  1. Pizza
  2. Pasta (=Spagettie & same type of food))
  3. Pannecakes
  4. Pommes frites (=french frices)

I use a extended bolus of 1.5 hours but is differend for everybody.

Most of my meals work out to roughly 30% carbs, 60% protein, 10% fat. As a matter of routine, I program in 75% of my insulin to be delivered up front, with the rest being delivered as an extended bolus over 2 hours. More protein or fat means I'll have more insulin extended for longer, and vice versa. The only time I will not program in an extended bolus is with a high carb snack, or the rare pure carb dessert which I will generally treat with a separate, additional, bolus

I shoot for post meal BG to be under 120 after 2 hours, and try to get back down to between 70 and 90 before the next meal, with an overnight average of 100 and a fasting between 70 and 90.

The extended bolus will put me in the ballpark, more or less. Most of the time, I'll have to correct, either with a snack or another bolus after 2 hours, but I'm generally close enough.

If I do not program in some kind of extended bolus before a regular meal, I'll crash before the 2 hour mark then spend the rest of the time on a roller coaster before the next meal.

Great point, I do use this as well from time to time for this purpose.

This is pretty good advice, and a good overview of the reasoning behind using an extended bolus (in terms of short- and long-term blood sugars after taking mealtime insulin).

I had posted this in another thread about the extended bolus feature as it relates to eating pizza and other high-fat foods, so maybe it'll help you out. This is obviously just a guideline and a description of how I go about using it:

"What I have always done, roughly, is this. Always a 50/50 split for carbs (any correction for BG should go in immediately obviously). Then 3 hrs for 10g fat - 14g, 3.5 hrs for 15g - 19g, and 4 hrs for 20g to eternity.

Obviously everyone is different, but I think these are good starting points."

I don't take protein into account at FHS does, but I'm sure it's just as valid. I've always found that fat is the big culprit for me, and working with my endo and dietician we decided this was the most effective method. YMMV, of course, so good luck experimenting!

Thanks markeezy. YMMV, no doubt. Whatever works and you definitely have a more precise and quantitative system for working out your extended bolus, but I'm absolutely sold on it's utility regardless of how people figure out how to use it.

I'm lucky that my meals are fairly consistent so that made trial and error a lot easier. I have no idea how it worked out to the extended bolus I ended up using but I feel like the gluconeogenesis from the protein is what mostly contributes to a spike later on post-meal for me. I definitely will have to put more insulin into my extended bolus if I increase the amount of protein, but 25% of the dose seems to be the magic number that puts me close to where I want to be if I just treat the carbs and roughly 25% of the protein as part of my total available glucose load.

At 10% of the meal, fat just seems to delay absorbtion without really adding to my insulin dose. At higher percentages, it does seem to add to my insulin need as well as the time it takes to absorb.

Then there are those days where it feels like I might as well just lick my finger and stick it into the wind.

yeah I had seen this in anther post, but I did not remeber where! Thanks for posting it again... I am going to give it a try as a starting point and work it out for me. Thanks again!!!

Happy to help! Good luck!

You know, I've never actually considered protein as part of the glucose load. That's an ineresting idea, and makes sense to me. I've noticed it happen with high fat from time to time, but I've never thought about the fact that protein could affect it as well. I notice when I eat a bunch of chicken and veggies for dinner occasionally my sugar goes waaaayyy higher than the amount of carbs consumed (hardly any) would dictate. I'll have to consider covering some of the carbs with insulin and see how it goes...

This might help!!


Super late response, but thanks for the resource! I still haven't had time to really check it out, but I joined the group! :)

I eat almost no carb and have to bolus pretty aggressively for protein. I try to stick to 40 g or less of protein at a meal and if it's a fatty meal, I will usually do 2.0 units over 2 hours, with just a little up front, maybe 15%. If it's not very fatty, then I'll do a little more up front, maybe 25% and only extend it for 1.5 hours. I may also adjust those numbers based on my current b/s even if it's fairly close to normal, like if I'm 130 I might up the total and the starting % a bit even though I wouldn't usually do a correction at 130.

Np, I don't post there much but people seem to be helpful and it's a great resource.

Good luck!!

I extend the bolus for popcorn. 20 - 30% in the trailers & the rest over the length of the film.