CGM: Trends, Alarms and Cost
Reviewed by CDE Mehandi Sharma · Updated
A continuous glucose monitor, or CGM, is a small sensor worn on the skin that reads glucose continuously and sends it to a phone or reader.
In Type 1 it does three things a fingerstick cannot. It shows the direction you are heading, not just where you are — a reading of 90 mg/dL means something very different rising than falling. It can alarm when you are heading low, including while you are asleep. And it fills in the overnight hours nobody was testing.
This is why CGM is particularly recommended for people taking insulin, and why it matters more here than in Type 2.
It also enables automated systems, sometimes called artificial pancreas systems, where a CGM and an insulin pump talk to each other and adjust background insulin without you doing the arithmetic.
The honest limitation in India is cost. Sensors are a recurring expense, usually paid out of pocket, and for many families diabetes care already consumes a very large share of household income.
If a permanent CGM is out of reach, a short period of sensor use is still worth discussing — two weeks of continuous data can answer a question that months of fingersticks could not.