Skip to content


Open-loop is a great place to start with Loop. When you are operating in open-loop mode, Loop is offering recommendations for insulin delivery adjustment and will display them on the main screen. The recommendations will not be enacted unless you specifically choose to enact it (tap on the recommendation on the HUD to enact it - phone must be held in portrait orientation). Usually in open-loop mode, you aren't really enacting the recommended basals but instead watching how the recommendations come in and figuring out WHY they are being recommended.

It is understandable to want to jump straight away into close-loop mode, but a lot can be learned by watching Loop operate in open mode. Becoming familiar with the algorithm can be easier by watching it in action rather than only reading about it in docs.


A great benefit of open-loop mode is that you can establish a baseline of BG trends without the influence of temp-basal or automatic-bolus from Loop. This is particularly helpful if you haven't used Medtronic sites/pumps or Omnipod prior to Loop. You may find that your basal rates change significantly coming from other brands of pumps or from multiple daily injections (MDI).

Taking the time to establish a good basal profile using the pump you plan to use for Loop will set you up for a smoother transition to closed-loop mode.

Test your insulin sensitivity factor (ISF) during open-loop time after your basal rates are established, as ISF is an important component for every Loop calculation for insulin delivery adjustment. Every 5 minutes, Loop uses your it's worth testing it ahead of closed-loop mode.

Eventual BG

One of the best things you can do is to train yourself to watch the eventual BG in addition to the current BG for helping understand Loop recommendations for insulin delivery adjustment. So many of us have become accustomed to dealing with current BGs and perhaps IOB at the same time...but Loop is also looking at BG momentum, carbs on board, retrospective trends. Loop is utilizing all of those variables to predict an eventual BG. Its current decisions are based on that eventual BG. Training yourself to watch that eventual BG will help you understand the temp basals being offered at any given time.

On the other hand, Loop will not recommend increased insulin delivery now if a temporary dip in BG is predicted; it may even be recommending a decrease, i.e., temp basal of 0 U/hr. So the eventual BG may be higher than you want, but if you see a dip below your correction range, pay attention over time. Once a dip is no longer predicted, then Loop will again recommend an increase in insulin delivery. If the Loop predictions don't match your experience - probably a sign that your settings may need to be adjusted.

Carb Absorption

Probably the next most difficult transition involves using carb absorption as a component to every meal entry. Similar to how you perhaps used extended boluses for meals that impacted BGs longer than the duration of your insulin...that same idea applies to estimate your carb absorption times. Watch your meals and try to estimate how long they are impacting your BG for various types of food. Watch the times when Loop would've wanted to suspend basal or increase insulin delivery...ask yourself why it would be doing that. Especially ask yourself if that is the same decision as you would've made at that time in a meal normally. Would you be worried that you might go low later if you see Loop offering increased insulin delivery early after a meal? Would you be worried about going high later if Loop wants to suspend basals instead? If you put some effort into this effort before closing the loop, it will pay off with a smoother transition to closed loop.


Get used to carrying the RileyLink around. Find how far your connectivity stretches before you have pump communication problems. Get used to troubleshooting yellow and red loops, finding out the pattern/cause of any potential loop issues. You'll be less frustrated starting on closed loop if you aren't dealing with learning new electronics at the same time as you are learning carb absorption times in a closed loop.


All new Loop users need to learn to bolus for meals by first entering carbs. For Medtronic users, do not enter carbs on the pump. For Omnipod users, learn how to use the Loop interface instead of the PDM. Become familiar with entering carbs into the Loop app, as well as editing them. Watch how long it takes for Loop app to display the bolus after you enact it. Familiarize yourself with the "Bolus May Have Failed" notifications and how to handle them. Double-check the pump and verify that the bolus didn't enact before trying to give the bolus again.

Learn about correction or manual bolus from Loop. If you manually enter a correction you think is right, but Loop (using the settings you entered) disagrees, it will probably recommend a 0 temp basal right away. It is OK to override Loop sometimes (e.g., a super bolus that trades bolus now for zero basal later) but you need to understand what you are doing and why. It's best to adjust settings rather than "fight" with Loop.

Caregiver training

If you are the caregiver of someone with Type 1 Diabetes using Loop, make sure you take the time to educate caregivers around your family and school (or other facility) for how to use Loop. Perhaps you want to draft individualized quick info sheets for those caregivers to use with Loop. If your child needs a site change at school, school staff or your child need to know how to handle that. Try to watch Nightscout while you get to know Loop so that you can become better at remote troubleshooting of any problems that you might encounter.

Back to top