MAUDE Adverse Event Report: Dexcom, Inc. Dexcom G6 Continuous Glucose Monitoring System

Model Number	9535-45
Medical Device Problem Code	Low Readings (2460)
Health Effect - Clinical Codes	Headache (1880); Hyperglycemia (1905)
Date of Event	09/13/2026
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that an inaccuracy between the continuous glucose monitor (cgm) and the blood glucose (bg) meter occurred.The sensor was inserted into the arm on (b)(6) 2026, which is off-label usage of the device.On the same day, it was reported that the patient experienced a cgm inaccuracy issue.Following completion of the sensor warm-up period and placement of a g6 sensor, the patient believed the sensor readings were inaccurate.The cgm reportedly displayed a glucose value of 95 mg/dl, which later decreased to approximately 70 mg/dl.Between approximately 11:00 am and 12:00 pm, the patient administered a gvoke hypopen glucagon injection, consumed honey, and ate a doughnut in response to the low cgm readings; however, the patient reported that the sensor values did not change following these interventions.At approximately 1:30 pm, the patient developed a headache and presented to a nearby fire department because no blood glucose meter was available.An emergency medical services (ems) obtained a fingerstick bg measurement, which reportedly showed 289 mg/dl, while the cgm reading was reportedly 188 mg/dl at the same time.Following the glucose measurement, the patient returned home and replaced the sensor.At the time of reporting, the replacement sensor was still in the warm-up period.No additional treatment, healthcare provider evaluation, emergency room (er) visit, hospitalization, or medical intervention was reported.It was reported that the patient was not using an insulin pump at the time of the event.At the time of reporting, the patient stated that there was no change in condition.No data was provided for evaluation.The allegation and the probable cause could not be determined.There was not a complete set of reported glucose values available to search within the parkes error grid calculator.When ems came, the reported glucose values fall within the b zone of the parkes error grid.There was not a complete set of reported glucose values available to search within the parkes error grid calculator.No additional patient or event information is available.
Additional Manufacturer Narrative
(b)(4).Diabetes mellitus is a known cause of hyperglycemia.

• Brand Name: Dexcom G6 Continuous Glucose Monitoring System
• Common Device Name: Continuous Glucose Monitor
• Manufacturer (Section D): Dexcom, Inc.; 6340 sequence dr.; san diego CA 92121
• Manufacturer (Section G): Dexcom, Inc.; 232 s dobson rd; mesa AZ 85202
• Manufacturer Contact: jaime chavez ; 6340 sequence dr.; san diego, CA 92121 ; +1(858)200-0200
• MDR Report Key: 50886754
• Report Number: 3004753838-2026-258941
• Device Sequence Number: 10707967
• Product Code: QBJ
• UDI-Device Identifier: 00386270000866
• Combination Product (Y/N): N
• Initial Reporter State: MD
• Initial Reporter Country: US
• PMA/510(K) Number: DEN170088
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Consumer
• Type of Report: Initial
• Report Date (Section B): 09/24/2026

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Operator of Device: Lay User/Patient
• Device Model Number: 9535-45
• Device Catalogue Number: STS-OE-003
• Device Lot Number: 7372694
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: No
• Initial Date Received by Manufacturer: 09/13/2026
• Initial Report FDA Received Date: 09/24/2026
• Was Device Evaluated by Manufacturer? (Y/N): No
• Date Device Manufactured: 10/07/2025
• Is the Device Labeled for Single Use? (Y/N): Yes
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Initial
• Patient Sequence Number: 1
• Concomitant Medical Products and Therapy/Usage Dates: Glucagon / Gvoke (Injection)
• Outcome Attributed to Adverse Event: Other
• Patient Age: 74 YR
• Patient Sex: Female
• Patient Weight: 300 LB