Delay of insulin action

I have been LADA for 35 years and just turned 70. I am still in good shape and exercise regularly. Lately, my “fast acting” generic humalog has more than a 1 hour delay in action. My wife thinks I have developed insulin resistance, but I am wondering if it may be slower digestion or circulation issues. I am wondering what other seniors are experiencing with this kind of delay and what you think the cause might be? (I prefer Novolog which acts faster for me but my Tandem pump supplier only provides generic humalog.)

1 Like

I am a senior, though several years younger. Almost 50 years of T1. Have not experienced this. Slower digestion does not make sense, if anything that would cause a low BG, not a high. I used Humalog for many decades, and find Novolog a 1 for 1 replacement, so personally would not think it is the insulin type. Also have found no difference between generic and name brand insulin versions.

Circulation slowing seems unlikely to me unless you are injecting into a compromised site. Might you have scarring or fat deposits at injection site? Maybe try different sites (abdomen, etc).

Finally insulin resistance seems like it would be causing increased insulin amount rather than slower timing? Maybe you have gained weight and simply need more insulin?

2 Likes

64, ~47 years with T1. I sense something similar, but I usually focus on the quality of the injection, meaning getting the location and depth right, plus activity level. I work as a software engineer, and on days I am super-focused on coding, I don’t move around, but taking a brisk walk, or even around the apartment, will get things moving.

A separate issue might be the combined effect of long-term and short-term insulins. When I switched to Tresiba from Lantus, the suggested dose was too high, and it made my short-term shots overly strong. When we lowered my Tresiba, my Humalog went back to affecting me normally.

Thoughts about what might have changed:

  • Have you changed your long-term insulin?
  • Have you gained weight?
  • If so, do you need a longer needle, or a change in injection site?
  • Are you as active as before, not just workouts?
3 Likes

A bit older than you but a LADA for only 19 years. Novolog reaches peak 1-3 hrs after injection or infusion while Humalog peaks in 30-90 minutes. Both begin action within 15 minutes. So, not seeing much blood sugar lowering for the first hour would not be considered abnormal. From the product sheet:

I have type 2, and my Humalog injections peak at around 65 minutes. Before that, like you said – not much blood sugar-lowering going on. I set an alarm so I can take action in case BG starts to go too low (which it does occasionally, even with insulin resistance).

I don’t think my body has changed but I can certainly back some differences with the various insulins. Background: 64, 53 years T1 (since 1972 or there abouts, too long ago to remember).

  • Novalin (i.e. GE but not GM insulin): ok.
  • Humalog (GE and GM): ok.
  • Fiasp (Novalog, which I haven’t used, with an accelerant): better.

This is with a pump (Omnipod Dash) and I did adjust the “insulin action time” appropriately.

So yeah; all the 'lins are identical, but Humalog and Novalog are not identical (otherwise they both couldn’t have got their patents) and it is reasonable to assume that different humans will have different responses as a result.

I don’t know if the accelerant applied to Novolog is what makes Fiasp better for me or if it is just Novolog that is better.

I do concur that the effective action time of anything is somewhere around an hour. I suspect that would apply to Lantus as well; it just takes that long for a large amount to traverse our skin!

The only way I can change that number - the delay - is by excercise. My wife insists we do this each day, and I am a healthier person and, in fact, a happier person as a result of this.

The above is the “counter” to the generic and not very helpful concept of “insulin resistance”. We can increase our “insulin sensitivity” and it does, somehow, seem to me to lessen the “time of action”, but not by much; 45 minutes maybe instead of 60.

Sorry, I’m science, not religion. In science there are only questions, no answers, in religion there are only answers, no questions.

@John_BowlerGE and GM insulin?

ChatGPT is my new friend who knows much more than me:

GE (Genetically Engineered) Insulin and GM (Genetically Modified) Insulin refer to the same concept: insulin produced using recombinant DNA technology. This process involves inserting the human insulin gene into bacteria (typically Escherichia coli) or yeast (Saccharomyces cerevisiae), which then produce insulin identical to naturally occurring human insulin.

Key Points:

  1. GE/GM insulin is also called “human insulin” because it is structurally identical to the insulin produced by the pancreas.
  2. It replaced animal insulin (from cows and pigs), which was used before the 1980s.
  3. Biosynthetic production ensures large-scale, consistent, and hypoallergenic insulin supply.
  4. Modern insulin analogs (e.g., rapid-acting and long-acting insulins) are also genetically modified for improved absorption and duration.
3 Likes

I’m still pretty much a beginner when using Artificial Intelligence or AI. I need to think in the same context that I used think of a google search.

I was aware of Humulin for many years while I was using Regular insulin derived from pigs. I should have switched to it instead. I switched to Humalog when it came out in 1997 or so.

GE and GM are new terms to me. I have long known insulins like Humalog as Rapid-Acting Insulin Analogs (RAIA).

I think each of us perceive when insulin starts to affect your glucose levels differently. I was taught way back when that insulin (like Humalog or Apidra) has on onset, peak, and duration times. I remember onset at 15 minutes, peak at 90 minutes and duration at 6 hours. Like most things about diabetes, there is no precision or repeatability in this. Just general rules.

So many things like exercise, sleep status, or stress can squeeze or stretch out these general times. An under-dosed basal insulin will lengthen, even eliminate, expected onset, peak, and duration times of a meal-time dose. There’s just as much art as there is science to insulin dosing.

2 Likes

I spent two years working with an artist, he’d design theater sets. I’d do lights, sound and carpentry with him for 4 shows a year. Many days he’d be angry with me, like walk out of the building angry and I never figured out why. The analogy to insulin dosing is a good one.

AI is a lot like a kid. They can string together words they have heard but it doesn’t mean they know what they are talking about. I’m not saying don’t use AI but skip to the source documents. We are in a super awkward time because all the internet search sites are more interested in advertising than they are in producing relevant results.

Insulin finally got reclassified as the biologic that it is in 2020. The massive delay is part of why so few generics, I mean interchangeable biolimilars, are available. I bet CDEs are loving trying to explain Insulin is Now a Biologic—What Does That Mean? | American Diabetes Association to patients.

@RLS1 Looking the people in my family who are now in their 70’s every one of them has reduced their activity. Not necessarily the time spent doing things but the intensity. I’m not talking exercise but the little everyday things. For example they take longer going up the stairs or they always find a chair when walking into a room instead of standing around and talking. Any chance you are doing the same? When you take insulin your body has to do something with it. If your body doesn’t need the energy from more glucose the insulin will just circulate until other cells turn the glucose unto fat. I admit its a gross oversimplification.

My usual strategy when using AI tools is to run Gemini and Copilot side by side - Edge has a great split window feature - and enter the same prompt in both. I review and compare, then use the one that seems the one most correct, appropriate, comprehensive, or best formatted. For general topics, one does need to be skeptical and cautious, and certainly not use it as the only source, but I also use it for code work.

I know what I am doing and have been creating applications for 20 to 30 years, so trust myself. Even then, I am often asking it to create ‘grunt’ code, simple, low-level stuff I would rather not spend the time writing, but sometimes I have had it create whole small applications, and that combined with my decade or more experience in that type of app (Windows/WPF/XAML), it makes the work very easy, reducing time to hours instead of days.

1 Like

Also a LADA. Always thought humalog took too long. Switched to their faster acting Lyumjev and have been very happy with how fast it acts. Used it I. My tandem pump. No problems. Now back on MDI. Pump was not for me. Had so much trouble with all Infusions sets. Would like to go back to the InPen but currently Medtronic doesn’t make a Lyumjev cartridge. Good luck

Perhaps you could try Metformin and see what it does for you. I know Ginger Vieira has had success. The Surprising Benefits of Taking Metformin for Type 1 Diabetes | Beyond Type 1

Thanks to everyone for some very creative and personal suggestions and experiences. I may just be impatient in waiting for insulin to take action but I will also ask my Endo about Lyumjev and if my Medicare supplement covers it! I will try to post some examples of what I see from my Dexcom and Tandem reports! More comments appreciated!

1 Like

We have way too little info to really know what is happening. (Are you eating, if so when and how much?) But it does seem likely you are being impatient and unrealistic about the speed of bolus action.

Did you wake up and bolus for food at 4:30? If so, looks like you didn’t pre bolus, but ate right away then decided to add another couple of boluses in less than an hour? If this is correct, consider pre bolus, and watch BG until it turns corner before eating, which should be in 20-30 min range, unless you are also fighting FOTF. Do you experience FOTF? If so, that needs additional insulin to counteract and can appear to be slowing the action of that first bolus.

Then you give another 2 unit bolus, right at one hour later, just as your BG seems to be leveling off from previous three boluses. That again seems too impatient, and indeed BG then starts to tank. Better to check levels at 60 to 90 min, and if leveling and starting down, then no need to add more fuel to the fire.

In addition, your basal seems quite low before you are waking up (.4 uph with shutoffs vs 1.1 uph). If so, the four hour action time of insulin means that your reduced basal can be contributing to the high you see when you first wake up. Might your basal need tuning?

Then what is the yellow area labeled 298 in your insulin delivery line? Is that algorithmic adjustment to insulin delivery, if so up or down (I haven’t used this reporting app so don’t know how to interpret).

Overall conclusion is, yes, you are likely being too impatient. Try lyumjev if you want. Try reading “Sugar Surfing”, still the best way to understand when to be patient and how to best use insulin action to your advantage.

I read all the replies. It’s very frustrating when things change. I seem to have the opposite problem. I have a tandem t:slim and I have been quite stable for several years without needing many adjustments in settings. Now I am experiencing low values approximately 1 hour after eating. I have to drink a little sprite or take a glucose tablet to prevent a sharp and rapid fall. Then within a couple of hours my BGs are too high. I have made some adjustments of my own regarding basal rates, carb ratios, and correction factors. Any thoughts?? I am inclined to think the carb ratios for my meals should be my main focus.

Jane, interesting to hear that you like using the Lyumjev. I was thinking of switching to it from my slower-acting Humalog, but read several posts complaining on various forums about Lyumjev injections stinging too much. Have you noticed that at all?

Good morning. Once in awhile may feel a sting when injecting. But not often. Nothing that would make me switch. When using a pump I never felt any stinging. Maybe you could try and switch back to humalog if you have adverse reactions? Hope this helps. Take care, Jane

Jane Cerullo

1 Like

Yes, I am going to adjust my basal and I backed down my insulin duration from 4.5 to 4. that with being more patient is definitely the path I should follow! Plus avoiding big carb loads whenever possible. thanks!

2 Likes

Thanks so much, Jane. I may have a discussion with my doctor about it.