Safety Profile
Is Hyperbaric Oxygen Therapy Safe?
Hyperbaric oxygen therapy (HBOT) has been used safely for decades across medical, clinical, and wellness settings. The U.S. Food and Drug Administration has cleared HBOT for 14 specific medical conditions, and it is administered routinely in hospitals, wound care centers, and home environments around the world. When used in FDA-cleared chambers and following established protocols, HBOT is considered safe and well-tolerated by the vast majority of users.
OxyHealth, the global leader in hyperbaric chamber manufacturing, has delivered over 19,000 chambers worldwide and maintains an exceptional safety record spanning more than 29 years. Every OxyHealth chamber is FDA 510(k)-cleared, built to ASME PVHO-1 pressure vessel standards, manufactured under ISO 13485 quality management certification, and features UL-listed electrical components. More than 3,000 physicians trust OxyHealth technology in their practices.
Like any medical device or therapy, HBOT may produce some side effects, though these are generally mild and temporary. Understanding what to expect before your first session helps you prepare and communicate effectively with your healthcare provider or chamber operator. The sections below provide a comprehensive overview of possible side effects, organized by how frequently they occur.
It is always important to consult with a qualified healthcare provider before starting any hyperbaric oxygen therapy protocol. Your physician can evaluate your individual health history, current medications, and any conditions that may require special consideration.
Generally Mild and Temporary
Common Side Effects
The following side effects are the most frequently reported. They are considered mild, typically resolve on their own shortly after a session, and often diminish with subsequent sessions as the body acclimates.
Ear Pressure and Barotrauma
The most commonly reported side effect is a sensation of pressure or fullness in the ears during the pressurization and depressurization phases. This is similar to what many people experience during air travel or scuba diving. The middle ear must equalize to match the changing pressure inside the chamber. Simple techniques such as yawning, swallowing, or the Valsalva maneuver (gently blowing with your nose pinched) can relieve this sensation. If equalization is difficult, the operator can slow the rate of pressurization to allow more time for adjustment.
Temporary Fatigue
Some people feel mildly tired or relaxed after an HBOT session. This is a common response and may be related to the body processing increased oxygen levels. The fatigue is generally short-lived and many users report feeling re-energized within a few hours. Staying hydrated before and after your session and allowing time to rest afterward can help manage this effect.
Mild Lightheadedness
A brief period of lightheadedness or dizziness may occur during or immediately after a session, particularly for first-time users. This is typically related to the change in atmospheric pressure and increased oxygen concentration. The sensation usually passes quickly after returning to normal atmospheric pressure. Moving slowly when exiting the chamber and sitting for a moment before standing can help.
Sinus Pressure
Similar to ear pressure, the sinuses may feel congested or pressurized during a session, especially during changes in pressure. People with pre-existing sinus congestion or a mild cold may notice this more. Ensuring your sinuses are relatively clear before a session and using decongestant spray if recommended by your physician can help minimize discomfort. If sinus pressure is persistent, discuss it with your healthcare provider.
Infrequent
Less Common Side Effects
The following side effects are reported less frequently. When they do occur, they are typically temporary and resolve after the treatment course is completed.
Temporary Vision Changes
Some individuals who undergo multiple HBOT sessions may experience a temporary shift in vision, most commonly a mild increase in nearsightedness (myopia). This is believed to be related to changes in the lens of the eye caused by prolonged exposure to elevated oxygen levels. The effect is generally reversible, and vision typically returns to its pre-treatment baseline within several weeks after completing a course of sessions.
This effect is more commonly associated with higher-pressure clinical protocols (above 1.5 ATA) conducted over many sessions. Users of mild portable chambers operating at 1.3 ATA are less likely to experience this effect. If you notice any changes in vision during a treatment course, inform your healthcare provider.
Claustrophobia
Some individuals may feel anxious or uncomfortable in the enclosed space of a hyperbaric chamber, especially during their first session. This is not a physiological side effect of the therapy itself but rather a response to the enclosed environment. The degree of discomfort varies from person to person and is influenced by chamber design and individual sensitivity.
OxyHealth designs its chambers with spacious interiors, clear viewing panels, and internal communication systems specifically to minimize feelings of confinement. The Vitaeris 320, for example, features transparent walls that allow natural light and a full view of the surroundings. Many users who feel apprehensive during their first session become comfortable within just one or two sessions. Operators can also adjust the pace of pressurization to help new users acclimate gradually.
Very Rare
Rare Side Effects
The following side effects are extremely rare and are primarily associated with high-pressure clinical protocols rather than mild portable chamber use. They are included here for completeness and transparency.
Oxygen Toxicity
Oxygen toxicity can occur when the body is exposed to very high concentrations of oxygen at elevated pressures for extended periods. It most commonly affects the central nervous system or the lungs. Symptoms may include nausea, muscle twitching, or breathing discomfort.
This risk is primarily associated with pressures above 2.0 ATA with pure oxygen delivery over prolonged sessions. OxyHealth portable chambers operate at 1.3 ATA with ambient air, which is well within safe parameters. Clinical protocols at higher pressures include strict time limits and monitoring to prevent oxygen toxicity. Proper adherence to prescribed session durations and pressures makes this an extremely unlikely occurrence.
Seizure
Seizures related to HBOT are extremely rare and are associated with oxygen toxicity at high pressures, typically above 2.0 ATA with pure oxygen. The incidence in clinical settings is reported to be very low. These events are typically brief and self-limiting, resolving once the oxygen exposure is reduced.
At the mild pressures used in portable hyperbaric chambers (1.3 ATA), this risk is considered negligible. Clinical facilities that operate at higher pressures follow established safety protocols, including continuous monitoring and prescribed session durations, to mitigate this risk. Individuals with a history of seizure disorders should discuss HBOT with their physician before beginning treatment.
Important Safety Information
Who Should Not Use HBOT
While hyperbaric oxygen therapy is safe for most people, there are certain conditions and circumstances where HBOT may not be appropriate. It is essential to provide your healthcare provider with a complete medical history before beginning any hyperbaric therapy protocol. The following are recognized contraindications and precautions.
Absolute Contraindications
- Untreated Pneumothorax: A collapsed lung that has not been treated is the primary absolute contraindication for HBOT. The pressure changes inside the chamber could worsen this condition.
Relative Contraindications
- Certain Medications: Some medications, including certain chemotherapy agents, may interact with elevated oxygen levels. Consult your physician if you are taking any prescription medications.
- Specific Lung Conditions: Conditions such as emphysema with air trapping or a history of spontaneous pneumothorax may increase risk during pressurization. Medical evaluation is recommended.
- Upper Respiratory Infections: Active sinus or upper respiratory infections may make equalization difficult and increase discomfort during pressure changes.
- Pregnancy: The effects of HBOT during pregnancy have not been extensively studied. Pregnant individuals should consult their physician before considering hyperbaric therapy.
Always consult your physician. This page is intended for informational purposes only and does not replace professional medical advice. A qualified healthcare provider can evaluate your complete medical history and determine whether HBOT is appropriate for your individual situation.
Engineered for Safety
How OxyHealth Minimizes Risk
OxyHealth has spent more than 29 years refining hyperbaric chamber design with a relentless focus on safety, quality, and user comfort. Every aspect of an OxyHealth chamber is engineered to minimize risk and maximize the treatment experience.
FDA 510(k)-Cleared
All OxyHealth chambers are cleared by the U.S. Food and Drug Administration as Class II medical devices, ensuring they meet rigorous safety and effectiveness standards.
ASME PVHO-1
Built to the American Society of Mechanical Engineers pressure vessel standard for human occupancy, the highest standard for hyperbaric chamber construction.
ISO 13485 Certified
Manufactured under the international quality management standard for medical devices, ensuring consistent quality from design through production.
UL Listed
All electrical components are tested and certified by Underwriters Laboratories for safety compliance, providing an additional layer of protection.
Built-In Safety Features
- Pressure relief valves that automatically prevent over-pressurization
- Gradual, controlled pressurization and depressurization cycles
- Emergency pressure release mechanisms accessible from inside the chamber
- Clear viewing windows and transparent walls for visibility and comfort
- Internal communication systems for contact with operators at all times
- Medical-grade materials and construction tested for durability and safety
Practical Advice
Tips for Your First Session
A little preparation can help make your first hyperbaric oxygen therapy session comfortable and effective. Here are practical tips to help you get the most out of your experience.
Equalize Your Ears
Practice equalization techniques before your session. Yawning, swallowing, or gently blowing with your nose pinched (the Valsalva maneuver) can help relieve ear pressure during pressurization. Let your operator know if you have difficulty equalizing so they can adjust the rate.
Stay Hydrated
Drink plenty of water before and after your session. Proper hydration supports your body in processing the increased oxygen and can help reduce post-session fatigue. Avoid alcohol and caffeine before a session, as these may contribute to dehydration.
Communicate with Your Operator
Do not hesitate to speak with your chamber operator at any time during the session. If you experience discomfort, feel anxious, or have difficulty equalizing, let them know immediately. Operators can adjust pressurization speed, pause the session, or provide guidance.
Wear Comfortable Clothing
Wear loose, comfortable clothing made of natural fabrics. Avoid wearing jewelry, watches, electronic devices, or anything metallic into the chamber. Bring a book, tablet, or other entertainment to help you relax during the session, which typically lasts 60 to 90 minutes.
Frequently Asked Questions
Hyperbaric Chamber Side Effects FAQ
The most common side effects of hyperbaric oxygen therapy are mild and temporary. They include ear pressure or discomfort (similar to what you experience during air travel), temporary fatigue after a session, mild lightheadedness, and sinus pressure. These effects typically resolve on their own within a short time after the session ends. Proper equalization techniques, staying hydrated, and communicating with your operator can help minimize these effects.
Yes, hyperbaric oxygen therapy is considered very safe when administered in FDA-cleared chambers following proper protocols. OxyHealth chambers are manufactured under ISO 13485 quality management standards and built to ASME PVHO-1 pressure vessel safety standards. OxyHealth has delivered over 19,000 chambers worldwide with an exceptional safety record spanning more than 29 years. As with any therapy, it is important to consult a healthcare provider before starting HBOT.
Some people experience ear pressure or mild discomfort during the pressurization and depressurization phases of an HBOT session. This is similar to the sensation of descending in an airplane. The pressure change can temporarily affect the eardrum and middle ear. Techniques such as yawning, swallowing, or gently blowing with your nose pinched (the Valsalva maneuver) can help equalize the pressure. If you have a history of ear problems or recent ear surgery, consult your physician before using HBOT.
Some individuals may experience temporary, mild changes in vision (typically a slight shift toward nearsightedness) during a course of multiple HBOT sessions. This effect is generally reversible and vision typically returns to its pre-treatment baseline within weeks after completing a series of sessions. The effect is more commonly reported with higher-pressure clinical protocols rather than mild portable chamber use at 1.3 ATA. If you notice vision changes, discuss them with your healthcare provider.
Individuals with an untreated pneumothorax (collapsed lung) should not use hyperbaric therapy. People taking certain medications, such as some chemotherapy drugs, should consult their physician, as elevated oxygen levels may interact with these treatments. Those with certain lung conditions, severe upper respiratory infections, or recent ear or sinus surgery should also seek medical guidance before starting HBOT. A thorough medical evaluation is always recommended before beginning hyperbaric oxygen therapy.
Oxygen toxicity is associated with breathing pure oxygen at very high pressures, typically above 2.0 ATA, for extended periods. OxyHealth portable chambers operate at 1.3 ATA with ambient air, which is well within safe parameters. At these mild pressures, the risk of oxygen toxicity is extremely low. Clinical chambers operating at higher pressures follow strict protocols to manage session duration and pressure levels. OxyHealth chambers include built-in safety features to maintain appropriate pressure at all times.
Some individuals may experience a sense of claustrophobia when first using a hyperbaric chamber, particularly in monoplace (single-person) models. OxyHealth designs its chambers with clear viewing panels, spacious interiors, and accessible communication systems to help minimize this concern. The Vitaeris 320, for example, provides a roomy interior with transparent walls that allow natural light and visibility. Many people who initially feel apprehensive become comfortable after their first session. Operators can also adjust the pace of pressurization to help individuals acclimate.
OxyHealth chambers are engineered with multiple safety features to minimize side effects and ensure a comfortable experience. These include pressure relief valves, gradual pressurization and depressurization controls, clear viewing windows, internal communication systems, and emergency pressure release mechanisms. Every OxyHealth chamber is FDA 510(k)-cleared, ASME PVHO-1 certified, ISO 13485 manufactured, and UL listed. With more than 29 years of manufacturing experience and over 19,000 chambers delivered worldwide, OxyHealth has a proven track record of safety and reliability.
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