Novolog, active insulin time

I am using novolog vs humalog now in my pump and have my active insulin time set for 4 hours. I have seen a lot of posts lately about novolog a strong tail. Wondering if I should increase the time in this setting.

I use Novolog in my pump and use 3.5, but may vary for you. My experience was that Novolog kicked in quicker than Humalog, but now it’s been many years since using Humalog in pump.

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I’m still figuring things out for me…so maybe stick with what you know until you see a reason to change it?

I still feel too new to FUD to give out advice…but I did see your question and since you’ve probably seen my experience with Novolog lasting stronger/longer for me, I wanted to at least acknowledge your question even if I don’t have the answer!

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We used 4-1/2 hrs for Novolog on the X2.

I think the delivery does matter. The tail on the Ping seemed shorter. Hard to recall now, but I think we had it set to 3 hrs although that was also Humalog with the Animas Ping.

Initially when switching to the X2, we were still on Humalog and needed to increase the insulin duration time up to 4-1/2 hrs. When we switched from Humalog to Novolog on the X2, we did not see a need to further change the duration of action.

I also think this is different from individual to individual.

And further, I think whatever garbage the manufacturers put out about how long it lasts is just that.

We are on Fiasp now (on the X2) and the duration is much shorter.

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I think my setting works well for me because my meals generally are lower carb, always with some protein and fat. So there may be a longer tail for me, but it’s used to balance that potion of meal, so I don’t need/want visibility to it on IOB.

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This is a tricky question because it has different consequences in different functions

The true duration of insulin action is very useful to know how and when to stack. For us, DIA is about 5.5 hours, and, if we stack, we can go low 5.5 hours after an injection.

But, in a pump, when you use the calculator, it will often take out the amount of IOB you have left from your last injection to calculate your next bolus. Worse, some pumps use linear models and therefore assume that a lot more is left than is really the case (because the way insulin is used us not linear: more of it is used early). So you have to do some creative lying to your pump. Many endos recommend between 2 and 3.5 hours.

We use 3 hours in our pump. But we also don’t use the bolus calculator: we do all the calculations ourselves. This way the pump will not change the dose we enter. YDMV of course.