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Continuous Glucose Monitor (CGM)

What is a continuous glucose monitor (CGM)?

A continuous glucose monitor (CGM) is a wearable device that automatically tracks blood glucose levels at all times, day and night.

It uses a small sensor placed under the skin, often on the arm or stomach. This sensor measures the interstitial glucose level, or the amount of glucose in the fluid between cells. The continuous glucose monitor tests glucose levels every few minutes, and its data is then transmitted wirelessly to a monitor.

Sometimes, a continuous glucose monitor is combined with an insulin pump, which injects insulin based on the recorded glucose levels.

Some continuous glucose monitors require calibration twice a day. For this, the user tests a drop of their blood on a standard glucose meter and compares it to the continuous glucose monitor to ensure they are close.

How does a continuous glucose monitor improve healthcare?

The greatest benefit of the continuous glucose monitor is that it allows those with diabetes to see their glucose level at any time and look for trends over a few hours or days.

Continuous glucose monitors may also have an alarm that sounds when glucose levels are too low or too high. Since it records glucose levels every few minutes, the device can detect these abnormal readings quickly, allowing patients to remedy them immediately. The device can also be configured to send this data or alerts to another smartphone, such as the parent of a child with diabetes, allowing them to receive an alert when their child’s blood sugar levels are abnormal.