Common terms

Coefficients

ISF – Insulin Sensitivity Factor
I:C – Insulin to carbohydrates ratio

Active insulin or Insulin On Board (IOB)

IOB = IOBcarb + IOBcorr + RemainingExtendedInsulin – Insulin On Board or Active Insulin
IOBcarb – active insulin from carbohydrates
IOBcorr – active insulin from previous correction
RemainingExtendedInsulin – the remaining amount of the extended bolus

The IOB calculation is based on the curve shown in 9.2 Active insulin topic.

The algorithm to split IOB to IOBcarb and IOBcorr is:

→ IOBcarb = 0
→ IOBcorr = 0

FOR all entries in the last 8 hours DO
    → Calculate *bolusPercent* from the time of the entry to the current time, 
      according to the IOB curve for the selected active insulin duration

    IF entry has carbohydrates THEN
         → carbBolusIOB = min(bolus, carbohydrates/I:C) * bolusPercent
         → corrBolusIOB = bolus * bolusPercent - carbBolusIOB

    IF  entry doesn't have carbohydrates THEN
         → carbBolusIOB = 0
         → corrBolusIOB = bolus * bolusPercent

    → extendedInsulinIOB = 0

    IF  entry has extended insulin THEN
        → Calculate *extendedInsulinIOB* according its duration and current time

    → IOBcarb = IOBcarb + carbBolusIOB + extendedInsulinIOB
    → IOBcorr = IOBcorr + corrBolusIOB
END

→ IOB = IOBcarb + IOBcorr
Last modified: 2018/11/22

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