A continuous glucose monitor (CGM) sensor is a medical device that lets you track your glucose levels without a single finger prick. Our programs use the FreeStyle Libre sensor manufactured by Abbott Labs, which is designed to work for 14 days, automatically reading your glucose level every 15 minutes, or 96 times a day and 1,344 times over a 2-week period. In comparison, the traditional finger prick method results in only a single blood glucose measurement each time.
It is a small, disc shaped device that has been designed to be self-installed to the back of your upper arm. A thin filament attached to the sensor is inserted just under the layer of skin to measure interstitial fluid (ISF), a reliable indicator of blood glucose levels. ISF glucose changes when blood glucose levels change, but usually with about a 5-10 minute lag. The average lag time of the FreeStyle Libre system relative to a blood glucose level change is approximately 5 minutes.