30-Day Supply Quantity for Dexcom Sensors
A 30-day supply of Dexcom sensors is 3 sensors, as each Dexcom sensor is approved for 7-10 days of wear depending on the model.
Sensor Wear Duration by Model
Based on the available evidence, Dexcom sensors have specific approved wear times 1:
- Dexcom G4 and G5: 7 days of wear
- Dexcom G6: 10 days of wear
- Dexcom G7: 10 days of wear (labeled duration)
Standard 30-Day Supply Calculation
For Dexcom G6 and G7 (10-day sensors):
- 3 sensors = 30 days of continuous coverage
For older Dexcom models (7-day sensors):
- 4-5 sensors would be needed for 30 days of continuous coverage
Important Clinical Reality
Real-world sensor wear is typically shorter than labeled duration. A 2025 study found that among youth with type 1 diabetes using Dexcom G7, the median actual wear time was only 8.6 days (not the labeled 10 days), with just 39.9% of sensors worn for the full 10 days 2. This means patients may require 43 sensors per year rather than the standard 36 sensors (based on 10-day wear) to maintain continuous use 2.
Prescribing Recommendations
For insurance and prescription purposes:
- Prescribe 3 sensors per month for Dexcom G6/G7
- This aligns with the FDA-approved 10-day wear duration per sensor
- Document if patients require additional sensors due to early sensor failures, skin reactions, or other issues requiring premature removal
Common pitfall: Insurance typically covers 36 sensors annually (3 per month × 12 months), but real-world use often requires more due to sensors failing before the labeled duration expires. Be prepared to document medical necessity for additional sensors when needed.