Calibration Overview; How Do I Calibrate? - Dexcom G5 User Manual

PRECAUTION
Do: Only use fingerstick measurements from your BG meter for calibration.
Don't: Never use alternative site BG values such as blood from palms, forearms, etc.
Why: Alternative site BG values are different from a fingerstick BG value and may not
reflect most recent BG value.
Consequences: Missing a severe low or high glucose event or making a treatment
decision that results in injury.

7.3 Calibration Overview

What Is a Calibration?
As you learned earlier, the sensor glucose readings come from measuring the glucose
found in fluids between your cells (interstitial fluids). Although blood and interstitial fluids
are similar, sensor glucose readings can be different between your fingerstick and your
CGM. Calibration provides a comparison, or measurement, between your meter's fingerstick
measurement and the sensor's glucose readings, allowing alignment between the sensor and
meter.
Your BG meter "teaches" the sensor your glucose values through calibration. Just like a clock
can need adjusting, calibrations allow your CGM to adjust to your body.
Why Is Calibrating Important?
Calibrations are a must to make sure the CGM system is performing at its best.
By calibrating when the system notifies you that a calibration is due, the Dexcom G5 Mobile
uses your meter's BG value to make sure the sensor glucose readings remain accurate
throughout your session.

How Do I Calibrate?

Take a fingerstick measurement from your meter, and simply enter the meter's BG value into
one display device.
When taking a fingerstick, it's important to do it correctly. Make sure you wash and dry your
hands right before. And remember: always use your finger, never another site.
Dexcom G5 Mobile System User Guide
Calibration 98