How often should patients change their Dexcom (Continuous Glucose Monitoring) CGM sensor?

How Often to Change Dexcom CGM Sensors

Dexcom continuous glucose monitoring (CGM) sensors should be changed every 7-10 days, depending on the specific model being used. 1

Dexcom Sensor Wear Duration by Model

• Dexcom sensors have manufacturer-specified wear periods that range from 7-10 days 1:
  • Older Dexcom models: 7-day wear period 2
  • Current Dexcom G6: 10-day wear period 1
  • Dexcom G7: 10-day wear period 1

Importance of Timely Sensor Changes

• Regular sensor changes are essential for maintaining accuracy and reliability of glucose readings 1
• Sensor accuracy may decline over time, with some studies showing varying performance throughout the wear period 2
• Interestingly, some studies have found that accuracy can actually improve by day 7 compared to earlier days, with mean absolute relative difference (MARD) being lowest on day 7 in some evaluations 2

Factors Affecting Sensor Performance

• Sensor performance can be affected by several factors that may necessitate earlier replacement 1:
  • Skin irritation or allergic reactions at the insertion site 1
  • Physical displacement or damage to the sensor
  • Exposure to interfering substances that may affect glucose readings 1
  • Persistent inaccurate readings compared to fingerstick measurements

Best Practices for Sensor Changes

• Patients should not allow gaps in CGM coverage to ensure continuous monitoring and optimal diabetes management 1
• When changing sensors, it's advisable to:
  • Insert the new sensor before removing the old one to avoid gaps in data collection 1
  • Follow manufacturer's instructions for proper insertion technique
  • Rotate insertion sites to prevent skin irritation 1
  • Have backup supplies available to ensure uninterrupted monitoring 1

Common Pitfalls to Avoid

• Extending sensor wear beyond the manufacturer-recommended period may lead to:
  • Decreased accuracy of glucose readings 1
  • Increased risk of skin irritation or infection 1
  • Potential loss of warranty coverage for the device
• Calibration requirements vary by model - newer Dexcom models (G6, G7) are factory-calibrated and generally don't require fingerstick calibrations for treatment decisions 1

Special Considerations

• For optimal benefit, CGM devices should be worn as consistently as possible, with minimal interruptions 1
• Intermittently scanned CGM devices should be scanned at minimum once every 8 hours to avoid data gaps 1
• Patients should be educated on potential interfering substances and other factors that may affect accuracy 1