What are the differences between interstitial fluid (ISF) and blood glucose (BG) readings?
Interstitial fluid glucose measurements are taken from the fluid within tissue while blood glucose measurements are taken directly from the blood.
Sensor glucose values, which are based on interstitial fluid glucose levels, can be different from blood glucose levels (fingersticks), particularly during times when your blood glucose is changing quickly. For example, after eating, taking insulin, or exercising. When glucose levels are falling quickly, glucose readings from the sensor may be higher than blood glucose levels. On the other hand, when glucose levels are rising quickly, glucose readings from the sensor may be lower than blood glucose levels. To learn more about sensor glucose vs. blood glucose, please visit our "CGM vs Blood Glucose Monitoring" page.
If your glucose readings and alarms from the system do not match your symptoms or expectations, use a fingerstick blood glucose value from a blood glucose meter to make diabetes treatment decisions1.
Sensor glucose values, which are based on interstitial fluid glucose levels, can be different from blood glucose levels (fingersticks), particularly during times when your blood glucose is changing quickly. For example, after eating, taking insulin, or exercising. When glucose levels are falling quickly, glucose readings from the sensor may be higher than blood glucose levels. On the other hand, when glucose levels are rising quickly, glucose readings from the sensor may be lower than blood glucose levels. To learn more about sensor glucose vs. blood glucose, please visit our "CGM vs Blood Glucose Monitoring" page.
If your glucose readings and alarms from the system do not match your symptoms or expectations, use a fingerstick blood glucose value from a blood glucose meter to make diabetes treatment decisions1.