What is the difference between a Dexcom CGM sensor glucose reading and blood glucose value (BGV)?

Dexcom CGM systems measure the glucose levels in the interstitial fluids just beneath your skin. Blood glucose meters measure glucose levels in your capillary blood.
Different body fluids give different numbers due to physiological reasons, so readings between the two will rarely be exactly the same. However, if your sensor readings do not match your symptoms:
  1. Wash your hands with soap and water
  2. Dry them
  3. Take a fingerstick with your meter
If your meter value matches your symptoms, use it to make treatment decisions. You may find more information on accuracy for your Dexcom system here: What should I do if my sensor reading and blood glucose value don’t match?

MAT‑11165

This device is a registered medical device under Act 737. MDA Registration No.: GC4609424-190288. Advertisement Approval MDAMD 080/2026
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Dexcom, Dexcom ONE+ and any related logos and design marks are either registered trademarks or trademarks of Dexcom, Inc. in the United States and/or other countries.
Always read the label and use only as directed. Read the warnings available on dexcom.com/downloadsandguides before purchasing. Consult your healthcare professional to see if this product is right for you. This product is a continuous glucose monitoring system indicated for the management of (type 1, type 2, gestational) diabetes in people age 2 years and older where self-monitoring of blood glucose (SMBG) is indicated.
This device is a registered medical device under Act 737. MDA Registration No : GC4609424-190288

MAT-12312

• MAT‑11165

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