Large changes in carb ratios, and ISF, with loop?

I’ve been running the loop/omnipod for about 2.5 weeks now. At first, my control was way off compared to my Tandem G4. Loop was pushing a lot of temporary basal rates at the maximum to get my sugars down.

I’ve adjusted carb ratios now to be much lower (1:9 from 1:14), and actually reduced basal a tiny bit. I also increased ISF (1:35 from 1:50).

I’m getting closer to the ‘right’ ratios and ISF, but its surprising me how much I’ve had to change! Anyone else having the same experience? I guess its possible that this is just an artifact of going to the omnipod.

I certainly had that experience when I started that Medtronic 670g. My basal went way down, my sensitivity way down and my carb ratios way up. Overall it dropped my insulin usage by 1/3.

Note: I am a Medtronic ambassador. My opinions are my own. They did not pay me to say nice things about Medtronic devices or the company. OK, they sent me a shirt and a cup but even I am more expensive than that.

I’ve been looping for close to a month now. I had already been using OmniPod. But I, too, have had to adjust my carb ratios from 1:15 to 1:10 to try to even out Loop’s temp basals. I haven’t changed basal or ISF much though. I’m still watching everything very carefully though so may still make changes.

Unfortunately, right now, I continue to have OmniPod absorption problems or perhaps it is just insulin resistance. It seems like on each new pod, my insulin resistance shoots up and boluses seem to have no effect whatsoever, that I’m now resorting to syringe injection.

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@Trying I went through the same thing. I bolus via injection and switched my pod placement to areas where I hadn’t placed them much before and those two things did the trick, for now. It’s been over a year since I made these changes and I think I might have had one pod placement that gave me trouble. I’m still using the pods because I like how it controls my basal and keeps me flat. Unfortunately, I’m having absorption problems from the syringe now though, but that’s another health-related story!

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Thanks for confirmation that this issue exists!! :face_with_raised_eyebrow: It is a bit inconvenient to have to bolus with vial and syringe with Loop but I can enter the bolus via Apple Health, so it is doable. I’ll just have to carry both syringe and vial which I currently do not do! :frowning:

I’ve searched in this forum and here is an old thread on this subject. Most people suggest that this issue is related to bubbles. So next pod change I will try their suggestions.

Oh, man, I hope you resolve the absorption issue with the syringe!

I’ve been using Loop on an old Med-T pump for over two years now. I don’t feel 100% competent on tweaking various pump settings but I’ve done well enough.

You may want to read some of Katie DiSimone’s tips about adjusting basal rates, insulin to carb ratios, insulin sensitivity factors and duration of insulin action.

Complicating this is the reality that these factors are not a “set-it-and-forget-it” situation. Our bodies are dynamic, not static, systems. I think successful use of Loop as it now stands requires making adjustments to these settings on a regular basis.

Here’s some more good info from Katie on why and how to make these changes. In this column she address the transition from a SugarSurfing/Juicebod sensibility to effective use of Loop.


That’s good to know on the ratio adjustments. I’ve never had to adjust mine nearly as far as they are now, which is why I posted the question.

Sad to hear on the absorption issues! Using a syringe seems so old school with the fancy loop running :slight_smile:

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I just wanted to share this link which may help you with absorption issues. I changed my pod last night and tried Mark’s 3 step technique (warming insulin, keep syringe inverted to accumulate bubbles near plunger, inject slowly into pod, then after change, inject 0.5U) to help prevent bubble formation in the reservoir. So far, it seems to really have helped!! Instead of a total of 9-10U overnight basal after a change, I’m back to normal total of 2U overnight basal as calculated by Loop. I’m not certain this is a panacea, so I’ll see how the rest of the day goes, so far so good though.


@Trying Thanks for this! I’m not having any problem with my basal delivery since I moved off of my belly. I pretty much already follow Mark’s 3-step technique, except I don’t inject any insulin afer I change my pod; I never have. I’ve never noticed any problem with delivery after a pod change, but that could be for multiple other reasons. Yesterday after I changed my pod I was high at the 90-minute check, but I had eaten and deduced I didn’t bolus enough or it just wasn’t absorbed. It could have been from the pod change, so I’ll have to pay attention to that now and try to change the pod when I’m not planning on eating/correcting before the 90-minute check.

I’m not able to see the link you sent, as I’m not a member. I reread my original post and I was remiss in not mentioning I am not looping … yet. I want to, but the cost is a factor for us right now. I now see the post title, “… with loop?” which seemed to go over my head when I posted!

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That’s okay. I don’t think the OmniPod change issue for me is specifically a Loop issue. Though per Mark’s comments in the above link, Loop might increase the occurrences of bubbles with its constant shifting to zero temp basals when necessary, which may cause less back pressure giving opportunity for bubble formation. Or at least that is my interpretation of his remarks.

I’m glad to know that others revert back to syringes, too, on occasion.

I continued having insulin absorption issues during my run today. Usually I do a zero temp basal but today I noticed I was going high so I cancelled the override during the run to let Loop revert back to my nirmal basal. This probably has nothing to do with pod change though, pribably insulin resistance for some other reason!!

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