What type of insulin is best for AAPS insulin pumps?

I have been using Humalog with my Omnipod using the AAPS algorithm. I was wondering from your experience from using these automated algorithms. What insulin performs the best. I just dont think Humalog is the quickest when it comes to fast acting insulin.

I don’t think there’s a such thing as “best for AAPS”, given that there’s a setting to specify exactly what type of insulin you’re using so the insulin action algorithm matches your reality. In the config builder, under the insulin setting, do you have “rapid-scting 0ref” selected?

It’s more about timing things correctly. Do you pay attention to your IOB graph vs your BG? If you’re BG is spiking before the insulin action graph spikes, then you’re just not pre-bolusing soon enough, or not setting an eating soon temp target appropriately. It doesn’t necessarily mean your Humalog isn’t a good match for AAPS, but rather that you’ve not yet learned to match your behavior to the insulin.

Now there may absolutely be a better insulin for YOU, if not specifically for AAPS. Humalog, Novolog/NovoRapid, and their generic equivalents are considered rapid-acting insulins. (Rapid compared to the Humalin R that was previously used.). Medical and insurance people will tell you Humalog and Novolog are identical and interchangeable, but the actual patients know this often isn’t true. Personally, I DESPISE Humalog. It’s like injecting water. Novolog works so much better for me, but there are others who prefer Humalog. Now we also have newer insulins which are considered to be Ultra Rapid-Acting, because they work even faster than Humalog and Novolog. This category includes Lyumjev, Apidra, and FIASP. The base insulin is very similar to Humalog or Novolog, with extra added ingredients to make them work faster. So you if you have a preference between Humalog or Novolog, you might want to stay within the same manufacturing family.

There isn’t actually a massive difference between the rapid-acting insulins and the ultra rapid-acting ones. The newest ones peak in activity about 15 minutes sooner, though that varies greatly between individuals. Many report no difference at all, or that they work noticably faster in the initial weeks/months, but quickly lose all effectiveness shortly thereafter. Maybe that 15 minutes is really important to you, though. The only way to know if you like them is to try them for yourself. Unfortunately, depending on your insurance, access may be limited. I would like to try Lyumjev, since it seems to be the most favorably received, but it isn’t on an accessible tier on my insurance formulary. It requires a prior authorization and to get that you have to demonstrate failed treatment with the preferred insulins first. Since I’ve got good numbers and no undesirable side effects, I don’t qualify.


Tha k you for the detailed response. I do have that setting correct in config. The issue is what insulin the insurance will cover. I will look into Lyumjev. I think that one is covered.

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It really depends a lot on YOU and what your body likes. Everyone is a little different and you’ll have to experiment. :grimacing:

My experience is similar. I pay oop for novolog since humalog is on insurance but not novolog. But use a discount card for novolog.

Humalog works faster than novo log for me. My insurance dropped humalog for a while and forced me into novolog. And then after a few years they switched back to humalog.
In reality they are both very similar and I’m happy to use either.

I haven’t tried either of the fastest ones yet, but they need to solve the clogging and all that before I would bother pumping w it.

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FWIW, I’ve been pumping Fiasp for about four years and haven’t experienced any of those issues. I was a little concerned about it with switching to a Tandem pump because I’d Heard Things, but It’s been three weeks and no problems. I asked about it during the decision process because the informational materials specify that you should only use Novolog or Humalog, but the representatives assured me it wasn’t really a problem, just an FDA thing. My Tandem trainer has been using Fiasp for years in her T:Slim pump, so that was reassuring as well.

Re Fiasp “fade,” that’s obviously different sort of issue, being dependent on individual metabolism rather than the pump mechanism. Enough people report it that I have to acknowledge it’s a thing, but for my part I still find it faster than the two leading analogs. Still not as fast as I’d like sometimes, but I was at a point with the others where I was waiting 45 minutes or more before my curve would start to bend. They seemed much more susceptible to things like stress level. Fiasp seems much more stable and reliable in that respect for me.

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I think those points are well taken, but I would argue for an additional measure of success that is necessarily subjective: quality of life. A few years ago someone here linked to a study indicating that the outcomes for T1s using basal-bolus MDI were not all that markedly better than for those using the old R/NPH regimen. Having been on the latter for twenty years before finally getting switched to carb-counting with Lantus-Novolog, the difference in quality-of-life was enormous. I remember sitting there literally weeping at my desk the day I was able to keep working past my previously hard-wired lunch time and nothing happened!!! I still have some bitter feelings toward the non-specialist PCPs I had (HMO wouldn’t do a referral to an actual endo) who kept me on the old regimen for years, despite my pleas, because “Your numbers are fine let’s not change anything.” I.e., “We’re deeply uncomfortable with this whole insulin-T1 thing and let’s not rock OUR boat just cuz you want to try something you think you might like better.”

Switching to Fiasp was not nearly so epochal an evolution for me, but it does make things easier in terms of meal-blousing in time to limit post-prandial peaks. I haven’t kept exhaustive data on it but I could see the effect in my CGM tracks compared to how I was responding on Novolog, and those don’t seem to have altered significantly since going on it, so I prefer to stick with it. As a quality-of-life matter, it just seems to make things a bit easier.

Funny, I’d expect as one has less to lose, risk tolerance should go up!

But then as I further consider this tiny snippet (taken out of context from your comment) it is clear that the risk would remain great and the expected benefits reduced since there’s less time to realize the benefits.

Anyway sorry, didn’t mean to derail the conversation.

Done and done.


I actually linked the wrong study up there. I had meant to link this one from the New England Journal of Medicine.


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