Dexcom G5 - Sensor Glucose Readings

Dexcom G5 Mobile System User Guide
350Troubleshooting
Sensor Glucose Readings
Device What you see Problem What you do
BG Meter
Sensor readings
and BG meter
glucose values
often don’t show
the same.
See Chapter 7.
Differences are not
uncommon.
Readings from different
body fluids reflect
different numbers:
Meter - from blood.
Sensor - from
interstitial fluid.
20/20 Rule
If the meter shows 80
or less, CGM should
read within ± 20 points.
If the meter shows
80 or above, the CGM
should read ± 20%.
Example: a 202 mg/dL
sensor reading and a
188 mg/dL glucose
meter value = a 7%
difference (this is still
considered accurate).
Outside of 20/20 rule:
Calibrate again.
App
Receiver
(Continued on next page)