How far in advance do you give your insulin?

I recently got a Dexcom CGM, and it’s been really interesting to watch my blood sugar reactions to food. Before the CGM, I checked my sugars every two hours, and doing that allowed me to correct if needed, and I rarely saw high numbers on my glucometer.

With the CGM, though, I see that my sugars go up to around 200 about an hour after eating, but then go back down to 90-100 within another hour or so. I give my shot about 20 minutes before I eat. This wasn’t anything I was ever aware of because of my glucometer testing, but now that I see it, I’d like to fix it.

Correcting when it’s at 200 won’t help, since that will just make me go low later…so should I give the pre-meal shot earlier, like 30-45 minutes before eating? (I use Humalog.)

I know it’s all variable based on the food I’m eating, but any general thoughts would be appreciated. Just as an example, this morning I was 108 when I woke up. I gave 6 units of Humalog, waited 20 minutes, and then ate plain oatmeal and yogurt. An hour later, I was 204; two hours later, I was 91.



This is a very interesting topic. I think the bloodsugar fluctuation you’re taking about is pretty normal for a diabetic. We have a hyper-response after breakfast, especially with grains. There has been some talk about type 1’s using amylin injections (another hormone made in the pancreas that we lack) to prevent spikes, but if your glucose is coming back down within 2 hours it doesn’t sound too bad.

The other thing is, is it the reading on your CGM (interstitial glucose) that you are looking at or are you getting a BG with your meter after 2 hours? See if there’s a difference. The insulin could be taking longer to get into the majority of your tissues, but it’s working well enough to affect your BG.

I eat the same breakfast every morning (a mix of bran, flax, oatmeal and cream of wheat and milk) and I have to exercise within 60 min to prevent too big a spike. It has been recommended that I wait 20 min after bolusing to eat, but I have never had enough patience in the morning! (I’m on Humalog by pump) When I was on injections I think I bolused twice a couple times so I decided to forget it.

Good point about the interstitial fluids, @MaggieJo. I always forget about that; I’ll check it tomorrow. Another suggestion I had heard from someone was to split up my breakfast (so, eat the yogurt or oatmeal at the normal time, and then an hour later, eat the remaining item). I’ll plan to give that a shot sometime this week, too. I also see my endo on Monday, so hopefully I’ll have a few different ideas to see if I can keep it in a normal range. And yeah, you’re right - it’s definitely not bad if it’s only in a two-hour range. This CGM is turning me dia-crazy with how much I’m trying to control the numbers!!

Yes, welcome to the CGM love-hate relationship! It does get easier!

Yes, sounds like you need to wait longer before eating, and/or eat slower. If you’re willing to experiment, I recommend you get samples of the other two rapid insulins (Novolog and Apidra) and give them a try (maybe a week each). Personally, I found that Apidra kicks in a whole lot faster for me, so I use that now and have much better results (in terms of avoiding spikes). Another possibility is to add something with a ton of fat+protein to the meal, but I’ve found there’s only so far you can get with that technique.

Oh, I should mention that I try really hard to avoid spikes (up then down), not because I’m worried about future complications, but because they make me feel really nasty. I guess I’m unusual; most people have no symptoms.

Thanks, @Aitrus72. I’m seeing my endo on Monday morning, so I’ll bring up those insulins as well. And you’re right about the fat/protein…when I eat omelets on weekends, this doesn’t happen. But since I eat low carb and exercise in the evenings during the week, I like to have all my carbs at breakfast and lunch so I have enough energy to work out at night. (Plus, oatmeal and yogurt are just so quick and easy.)

What’s your timeframe when using Apidra?

You’re welcome!

>Thanks, @Aitrus72. I’m seeing my endo on Monday morning, so I’ll bring up those insulins as well.

Make sure to insist on getting samples. The official line is that all three are equivalent, but practically speaking, there are really big differences for some people. You never know until you try!

>But since I eat low carb and exercise in the evenings during the week, I like to have all my carbs at breakfast and lunch so I have enough energy to work out at night. (Plus, oatmeal and yogurt are just so quick and easy.)

>You wouldn’t have to subtract carbs, just add fat. But yeah, the convenience thing is a big problem. The slowest-absorbing foods are definitely not grab-and-go. :confused: Best compromise I’ve found so far is a fruit, like an apple. Expensive to eat every day, but quick to grab, and absorbs way slower than processed things like yogurt and instant oatmeal. Btw, the list of things I (personally) have to avoid completely is: juice, cereal, instant oatmeal, sugared yogurt, frozen waffles. So much for easy breakfast :stuck_out_tongue:

>What’s your timeframe when using Apidra?

10 minutes wait, for an average meal. Sometimes none. Never more than 15 (or I would crash).

I can’t seem to get rid of my breakfast spike either. My only problem is that it takes me all morning to come down–I usually end up between 65-95 before lunch (at noon) when I eat breakfast at 8:00am. Being back to normal 2 hours later instead of 4 would be awesome. I’m interested in what other people’s ideas are though–maybe I can use some.

Most adult type 1s have some insulin resistance in the mornings. You can try giving your dose another 20 minutes earlier, but I don’t think you’re going to see the results you want until your drop the morning yogurt. It’s too carb-y with the oatmeal.

Could you try oatmeal and a hardboiled egg?

English muffin with peanut butter?

Crackers and cheese?

Anything that’s less carbohydrates with some protein will make it easier for your insulin to hit your blood stream at the same time the carbs do.

One other thing I’ve noticed is that I go high if I eat anything at all on weekdays. Think it’s stress between getting my family out the door and me to work on time. The morning spike doesn’t happen on weekends.

Thanks for those ideas, @jennagrant. Even though I know it’s not something to be seriously worried about, I’d still like to try to figure out a way to peak at a lower number. I’ll see how a hardboiled egg or maybe just a piece of toast works out.

I did test my sugars to compare the glucometer reading with the CGM reading, and they were pretty close. I talked to my endo this morning and she wasn’t concerned at all, so I guess I feel a little better about it. She said to remember that even non-diabetics have spikes like that here and there, and that the bigger concern is just the length of time that it stays up there. Given that my average is about 126, she wasn’t worried at all, and she also didn’t think that giving the shot earlier would help.

I did get a sample of Apidra, so I’ll see what I think of that.

I’ll try to remember to keep this updated, @KSmerk12, and keep track of what did/didn’t work. Hopefully it will help. What do you typically eat for breakfast?

Great, you’ve got some things to test out. :slight_smile: Make sure to tell us what does and doesn’t help. There aren’t enough threads like this on the internet.

As for normal people having spikes: I know that’s the official line, but I have my suspicions that it’s untrue, or at least misleading. I’ve tested (nondiabetic) family and friends a few times, including after meals, and seen nothing over 105. Some day I hope to convince a nondiabetic to wear a dexcom sensor for a few days and find out for sure. :stuck_out_tongue: For me it’s only an issue of curiosity. I have to avoid spikes, not because they’re unhealthy, but because they make me feel terrible and unable to work/study/do anything.

My usual breakfast is a low sugar cereal like Cheerios and light and fit Greek yogurt or a hard-boiled egg if I have any. Occasionally I stop at McDonald’s and get an egg white McMuffin (hashbrown optional). If I’m really running late I will have a Level protein shake or protein bar ( if you haven’t tried them) My other problem is that I shower in the morning and am disconnected from my pump for about 45 minutes

@Aitrus72, I have the same suspicion. Yes, there might be a spike, but it certainly is not up to 204!! (I’ve done the same testing thing to my family :slight_smile: )

Today I tried the Apidra. You’re right, it DOES work faster; I waited 10 minutes, but even with the different insulin, my spike was still the same. I started dropping below 70 about 3 hours after eating, which is a new thing, also; not sure if that’s an Apidra thing.

@KSmerk12, that sounds like a pretty normal breakfast. I do know that my sugars go high and stay high with any kind of cold cereal, though. (Which makes me so sad because I LOVE LOVE LOVE cold cereal.) I’m not on a pump, so I can’t say anything about the disconnection; I wish I could help!

Tomorrow I’m going to try splitting the meal: I’ll eat the oatmeal first, and then an hour later eat the yogurt.

Just as an update, in case anyone is following this:

  1. Splitting the meal HAS worked: Eating the oatmeal right away and the yogurt an hour later has worked really well; I peaked at 138. It’s a little bit of a pain because my commute is on a train, so I have to eat my yogurt on the go.

  2. Giving my shot earlier worked too, but at the expense of dropping low, so I won’t be doing that again. I gave it about 40 minutes beforehand and went down to about 40 before I ate. I also went a bit higher (peaked at 151).

  3. Oatmeal and two hard-boiled eggs also worked well for me today; I wasn’t hungry and it didn’t bring my sugars up. (I only went up to 124.) My concern with this meal is that it’s not as carby, so I’m not sure how energetic I’ll be tonight. But maybe a yogurt snack will work; I’ll give that a shot.

This is why I love diabetes! Well, not love, but this is why its better than other diseases.

Diabetes-related problems can usually be solved through creative problem solving. That’s cool that you figured out a couple options that help. Thanks for sharing what worked for you. Take care.

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Because of this thread, I talked to my doctor this week about trying Apridra. He said that in his experience it didn’t make much of a difference, but said that every patient is different. He said I could give it a try if I wanted to and prescribed me one bottle to try. I’ll see how it goes.

@jennagrant, me too! I don’t know that I would have come up with any of the ideas that actually worked. (As is typical for me, the one idea I did have, giving insulin earlier, just backfired, lol.)

@KSmerk12: the biggest thing I noticed was (1) the timing of giving my shot and (2) lower numbers 3-4 hours after eating. The lower numbers weren’t super low (60s), but enough that I think I’ll stick with Humalog. Keep me posted on how it works for you, though. Humalog and Regular (!!) were the only two insulins I had ever used. It was pretty exciting to have a new one to try out!