MAUDE Adverse Event Report: Dexcom, Inc. Dexcom G7 Continuous Glucose Monitoring System

Model Number	9500-161
Medical Device Problem Code	Incorrect, Inadequate or Imprecise Result or Readings (1535)
Health Effect - Clinical Codes	Hyperglycemia (1905); Irritability (2421); Cognitive Changes (2551); Confusion/ Disorientation (2553); Altered State of Consciousness (4589)
Date of Event	07/28/2026
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 frequently between (b)(6) 2026 and (b)(6) 2026.The patient was using an omnipod 5 pump at the time of the event.On (b)(6) 2026, the patient experienced cgm inaccurate readings and the reporter and the patient attempted to manage the situation at home for approximately one day.The spouse was unable to recall the exact cgm values but estimated a difference of approximately 20 to 30 mg/dl between the cgm readings and fingerstick blood glucose (fsbg) measurements.The reporter could not recall whether the cgm values were higher or lower than the fsbg values.The only glucose value recalled was an fsbg reading of approximately 400 mg/dl.During this period, the patient experienced symptoms consistent with hyperglycemia, including irritability, difficulty expressing himself, and speech that was difficult to understand.On (b)(6) 2026, due to ongoing concerns, the reporter transported the patient to the emergency department (ed).Upon arrival, the cgm continued to display inaccurate readings; however, the spouse was unable to recall the specific cgm values.She only recalled an fsbg reading of approximately 400 mg/dl.The patient was admitted to the intensive care unit (icu) and was treated with intravenous (iv) fluids and intravenous insulin for blood glucose management.The reporter was unable to recall any laboratory testing performed or provide laboratory results.On (b)(6) 2026, the patient was discharged from the hospital.At the time of the report, the patient was reported to be doing well.Data was evaluated and the allegation was undetermined.The probable cause could not be determined via data.It has been reported that there was a difference in readings of 20-30 points on (b)(6) 2026.There was not a complete set of reported glucose values available to search within the parkes error grid calculator from (b)(6) 2026 to (b)(6) 2026.The data investigation did not find blood glucose calibration values to compare to cgm values during the reported sensor session or the calibrations during the reported sensor session were in accurate range per device specifications.No additional patient or event information is available.
Additional Manufacturer Narrative
(b)(4).Diabetes mellitus is a known cause of hyperglycemia.

• Brand Name: Dexcom G7 Continuous Glucose Monitoring System
• Common Device Name: Continuous Glucose Monitor
• Manufacturer (Section D): Dexcom, Inc.; 6340 sequence dr.; san diego CA 92121
• Manufacturer Contact: jaime chavez ; 6340 sequence dr.; san diego, CA 92121 ; +1(858)200-0200
• MDR Report Key: 50675600
• Report Number: 3004753838-2026-245487
• Device Sequence Number: 5315879
• Product Code: QBJ
• UDI-Device Identifier: 00386270004116
• Combination Product (Y/N): N
• Initial Reporter State: TX
• Initial Reporter Country: US
• PMA/510(K) Number: K213919
• 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,Followup
• Report Date (Section B): 09/10/2026

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: 9500-161
• Device Catalogue Number: STP-AT-013
• Device Lot Number: 1825346001
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: No
• Initial Date Received by Manufacturer: 08/26/2026
• Supplement Date Received by Manufacturer: 09/09/2026
• Initial Report FDA Received Date: 09/08/2026
• Supplement Report FDA Received Date: 09/10/2026
• Was Device Evaluated by Manufacturer? (Y/N): No
• Date Device Manufactured: 12/01/2025
• 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: IV fluids; IV insulin; Omnipod 5
• Outcome Attributed to Adverse Event: Hospitalization; Other
• Patient Age: 74 YR
• Patient Sex: Male
• Patient Weight: 148 LB