Affiliate Disclosure
This article contains affiliate links. If you purchase through these links, we may earn a commission at no additional cost to you. This does not influence our evaluations or rankings.
You cannot wear a Dexcom G7 continuous glucose monitor inside a hyperbaric chamber during treatment. The pressurized environment can damage the sensor, produce inaccurate readings, and potentially cause device malfunction. Dexcom’s official guidelines confirm that the G7 has not been tested or approved for use in hyperbaric conditions, and most treatment centers require patients to remove all electronic medical devices before entering the chamber.[1,4]
This creates a real challenge for diabetic patients undergoing hyperbaric oxygen therapy (HBOT), since blood glucose management during 60-90 minute treatment sessions is critical. Fortunately, several reliable workarounds exist that keep you safe without compromising either your glucose monitoring or your hyperbaric treatment.
What Dexcom Officially Says About Hyperbaric Use
Dexcom’s product labeling explicitly addresses environmental limitations for the G7 system. The user guide states that the device has not been tested in hyperbaric conditions and should not be used in environments where pressure exceeds normal atmospheric levels.[1]
This applies not only to medical hyperbaric chambers but also to any pressurized environment including:[1]
- Medical-grade hyperbaric oxygen therapy chambers (1.5-3.0 ATA)
- Mild hyperbaric chambers used at home (1.3 ATA)
- Commercial diving chambers
The same restrictions apply to other Dexcom models and competing CGM systems from Abbott (FreeStyle Libre 2, Libre 3) and Medtronic (Guardian 4). No continuous glucose monitoring system currently on the market has been validated for hyperbaric use.[2,3]
The Dexcom G6: The Only CGM With Published Hyperbaric Data
The G6 transmitter is the only CGM with published hyperbaric safety data. A 2020 study (PMID: 32176942) tested G6 transmitters through 11 pressurization cycles to 45 feet of seawater, finding no safety concerns, no structural compromise, and no NFPA 99 violations for battery-operated devices in hyperbaric environments.[2]
Important limitations apply: testing was conducted in multiplace chambers only, and a 2024 publication explicitly states that CGMs have not been validated for repeated hyperbaric exposure and should not be used in oxygen-pressurized monoplace chambers.[3]
Because the G7 is a different generation with different internal components, the G6 safety data does not apply to the G7.
Safe Blood Sugar Monitoring During Hyperbaric Treatment
Diabetic patients have several proven options for managing blood glucose around hyperbaric sessions. The key is establishing a monitoring routine that works before, during, and after treatment.[5]
Before Entering the Chamber
| Timing | Action | Target Range |
|---|---|---|
| 30 minutes before | Fingerstick blood glucose check | 100-250 mg/dL |
| 15 minutes before | Remove Dexcom G7 sensor | N/A |
| Immediately before entry | Confirm blood glucose, eat snack if below 120 mg/dL | 120-200 mg/dL ideal |
Most hyperbaric treatment centers recommend that diabetic patients enter the chamber with blood glucose between 120 and 200 mg/dL. Starting at the lower end of normal (70-100 mg/dL) creates risk of hypoglycemia during the session, since HBOT can lower blood glucose levels through increased metabolic activity.[5]
During the Session
Inside the chamber, fingerstick testing is not possible due to safety restrictions on bringing glucose meters and lancets into the pressurized, oxygen-enriched environment. This is why pre-session glucose levels matter so much.
If you experience symptoms of hypoglycemia during treatment, including sweating, dizziness, confusion, or trembling, communicate immediately with the technician monitoring your session. All accredited treatment centers have emergency protocols for diabetic patients, including the ability to stop the session and decompress safely.[4]
After Exiting the Chamber
Check blood glucose with a fingerstick meter immediately upon exiting. Many patients experience a glucose drop of 20-40 mg/dL during a standard 60-minute hyperbaric session, so having a snack available is prudent. You can reapply your Dexcom G7 once you have returned to normal atmospheric pressure.
Other CGM Systems and Hyperbaric Compatibility
No continuous glucose monitor is currently approved for hyperbaric use. Here is how the major CGM systems compare regarding hyperbaric restrictions:[2,3]
| CGM System | Hyperbaric Use | Published Safety Data | Notes |
|---|---|---|---|
| Dexcom G7 | Not approved | None | Remove before session; may need new sensor start after |
| Dexcom G6 | Not approved | Multiplace only (PMID: 32176942) | Same pressure limitations apply; G6 data does not apply to G7 |
| FreeStyle Libre 3 | Not approved | None | Adhesive may fail under pressure changes |
| Medtronic Guardian 4 | Not approved | None | Insulin pump must also be removed |
Managing Diabetes During Ongoing Hyperbaric Treatment
Patients undergoing multi-session HBOT protocols face unique diabetes management challenges. Many wound healing protocols require 20-40 sessions over several weeks, making sustainable glucose management strategies essential.[5,6]
Insulin Pump Considerations
If you use an insulin pump alongside your Dexcom G7, the pump must also be removed before entering the hyperbaric chamber. Insulin pumps contain electronic components and batteries not rated for pressurized environments, and insulin delivery rates may be affected by pressure changes.
Work with your endocrinologist to develop a protocol for treatment days. This typically involves switching to manual insulin injection on treatment days, adjusting basal rates before disconnecting the pump, planning treatment times to minimize disruption to your insulin schedule, and having rapid-acting insulin available for post-session corrections.
Blood Glucose Patterns During HBOT
Research suggests several common glucose patterns during hyperbaric treatment:[5,7]
- During sessions: Blood glucose tends to decrease by 20-50 mg/dL due to increased oxygen availability enhancing cellular glucose uptake
- Immediately after: A brief glucose spike (20-30 mg/dL) is common as stress hormones normalize
- Over the treatment course: Some patients report improved overall glucose control after 10+ sessions, possibly related to reduced inflammation and improved circulation
What to Ask Your Hyperbaric Treatment Center
Before your first session, ask these specific questions to ensure the facility can safely accommodate diabetic patients:[4]
- What is your protocol for diabetic patients during HBOT?
- Do you have glucose tablets or juice available in the chamber area?
- Can the technician communicate with me during the session if I experience symptoms?
- How quickly can you decompress the chamber in an emergency?
- Do you require specific pre-session blood glucose ranges?
- Have you treated other patients who use CGM systems like the Dexcom G7?
Reputable treatment centers will have clear answers to all of these questions. If a facility cannot articulate their diabetic patient protocol, consider finding a center with more experience managing complex patients. UHMS-accredited facilities are required to have these protocols in place.
Who Benefits Most From HBOT as a Diabetic Patient?
Hyperbaric oxygen therapy has FDA-cleared indications for specific diabetic conditions, and managing CGM devices around treatment is a manageable inconvenience for significant therapeutic benefit.[4,6]
HBOT is indicated if you have:
- Diabetic foot ulcers that have not responded to 30+ days of standard wound care
- Wagner Grade III or higher diabetic wounds
- Compromised skin grafts or flaps related to diabetic vascular disease
- Diabetic osteomyelitis not responding to antibiotics alone
- Radiation injury to tissue (common in diabetic cancer patients)
Talk to your doctor first if:
- Your blood glucose is frequently above 300 mg/dL or highly unstable
- You have severe hypoglycemia unawareness
- You are considering home hyperbaric therapy without medical supervision
- Your A1C is above 10% and glucose management is not yet stabilized
Frequently Asked Questions
Can I Wear My Dexcom G7 in a Hyperbaric Chamber?
No. The Dexcom G7 must be removed before entering a hyperbaric chamber. The pressurized environment can damage the sensor, produce inaccurate glucose readings, and potentially cause device malfunction. Always check blood glucose with a traditional fingerstick meter before and after treatment.[1]
Will Hyperbaric Therapy Damage My Dexcom G7 Sensor?
Potentially yes. Pressure changes during compression and decompression can crack the sensor housing, displace the subcutaneous filament, and cause adhesive failure. Even if the sensor appears intact after hyperbaric pressure exposure, readings may be unreliable and should not be used for insulin dosing decisions.[2]
What Should My Blood Sugar Be Before Entering a Hyperbaric Chamber?
Most hyperbaric treatment centers recommend blood glucose between 120 and 200 mg/dL before entering the chamber. Starting below 100 mg/dL increases hypoglycemia risk, since HBOT can lower blood sugar by 20-50 mg/dL during a session. Always confirm protocols with your specific treatment center.[5]
Can I Use a FreeStyle Libre Instead of Dexcom in a Hyperbaric Chamber?
No. The FreeStyle Libre (all versions including Libre 2 and Libre 3) has the same hyperbaric limitations as the Dexcom G7. No CGM system is currently approved for use in pressurized environments. Fingerstick blood glucose meters remain the only reliable option for pre- and post-session monitoring.[3]
Does Hyperbaric Therapy Help With Diabetes?
HBOT has FDA-cleared indications for diabetic wound healing, specifically non-healing diabetic foot ulcers. Research shows that clinical-grade hyperbaric chambers delivering 2.0-2.4 ATA can significantly improve wound healing outcomes. Some studies also suggest improvements in insulin sensitivity and peripheral circulation, though these are not yet FDA-cleared indications.[6,7]
How Many Hyperbaric Sessions Do Diabetic Patients Need?
Typical diabetic wound healing protocols involve 20-40 sessions, usually 5 days per week for 4-8 weeks. Each session lasts 60-90 minutes at 2.0-2.4 ATA. Your hyperbaric physician will determine the specific number of sessions based on wound severity and healing response.[6]
Medical Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult your endocrinologist and hyperbaric medicine physician before making changes to your diabetes management during HBOT. Never adjust insulin doses or CGM usage without professional medical guidance.
- Dexcom. Dexcom G7 User Guide: Environmental and Safety Information. Dexcom, Inc. dexcom.com/en-us/safety-information.
- Fife CE, et al. Dexcom G6 transmitter safety in hyperbaric oxygen conditions. Undersea & Hyperbaric Medicine. 2020;47(1). PMID: 32176942.
- Katznelson R, et al. HBOT in Diabetic Patients: CGM considerations. Diving and Hyperbaric Medicine. 2024;72(1175). DOI: 10.28920/dhm54.1175.
- UHMS Safety Committee. CGM monitoring in hyperbaric environments. Undersea & Hyperbaric Medicine. 2020;47(1). uhms.org/images/MEDFAQs/Safety/2_272_CGM_monitoring.
- Hadanny A, et al. The safety of hyperbaric oxygen treatment: retrospective analysis in 2,334 patients. Undersea & Hyperbaric Medicine. 2016. PMID: 27265988.
- Löndahl M, et al. Hyperbaric oxygen therapy facilitates healing of chronic foot ulcers in patients with diabetes. Diabetes Care. 2010;33(5):998-1003. DOI: 10.2337/dc09-1754. PMID: 20427683.
- Kranke P, et al. Hyperbaric oxygen therapy for chronic wounds. Cochrane Database of Systematic Reviews. 2015;(6):CD004123. DOI: 10.1002/14651858.CD004123.pub4. PMID: 26106870.
Medical Disclaimer
The content on BaricBoost.com is for informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.
Author
Seph Fontane Pennock is the founder of BaricBoost.com and Regenerated.com, a clinic directory for regenerative medicine serving 10,000+ providers across the United States. He previously built and sold PositivePsychology.com, which grew to 19 million users and became the largest evidence-based positive psychology resource on the web. Seph brings direct experience as an HBOT patient, having completed protocols at clinics across three continents while navigating mold illness, systemic inflammation, and autoimmune conditions. His treatment journey includes hyperbaric oxygen therapy, peptide protocols, NAD+ therapy, and consultations with specialists from Dubai to Cape Town to Mexico. This combination of entrepreneurial track record and lived patient experience shapes everything published on BaricBoost.com. Every article is grounded in peer-reviewed research, informed by real clinical encounters, and written for patients making high-stakes treatment decisions. Seph's focus is on bringing transparency, scientific rigor, and practical guidance to the hyperbaric oxygen therapy space.
Why Trust Our Evaluations
Our rankings are based on hands-on testing, published clinical data, and verified manufacturer specifications. We apply the same criteria to every product regardless of affiliate status. Editorial Process · Evaluation Methodology
