Dexcom SEVEN User Manual page 50

The Seven System requires 2 BG fingerstick readings at the first calibration prompt. The
Receiver will prompt you for these readings about 2 hours after you insert a new Sensor
(see Section 3.1).
After you complete initial calibration you must update Receiver calibration a minimum
of once every 12 hours. The Receiver will request a new BG reading for calibration update
every 12 hours if you have not uploaded any BG readings before the 12-hour period.
NOTE
Do not use alternative site testing (blood from your palm or forearm, etc.) for
calibration. You must take your blood glucose from your fingertips only for calibration.
46 | SEVEN CONTINUOUS GLUCOSE MONITORING SYSTEM
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