Most patients who walk into RevitalizeMe for their first hyperbaric oxygen therapy session tell me the same thing afterward — it was nothing like what they imagined.

They expected something intimidating. Something cold and clinical. Something that would make them feel confined or anxious. What they found instead was a quiet room, a comfortable chamber, and a team that walked them through every step before anything started.

My name is Dr. Cyrus Garmo. I am board-certified in Internal Medicine and certified in Hyperbaric Medicine through ATMO, recognized by the Undersea and Hyperbaric Medical Society. At RevitalizeMe Hyperbaric Oxygen and Wound Care in Saginaw, Michigan, I have watched the anxiety leave patients’ faces the moment they actually see the chamber and understand what the session involves. I am writing this because I want that moment to happen before you arrive — not after.

If you have been referred for hyperbaric oxygen therapy, or if you are considering it and want to know what you are actually signing up for, this is the article I wish every patient could read before their first appointment.

In this article:

• Why patients are often nervous before their first session and why they do not need to be
• What happens before you ever get in the chamber
• What the chamber actually looks and feels like
• What happens during your session minute by minute
• What you will feel inside the chamber
• What happens after your session ends
• How to prepare — a practical checklist

Why Patients Are Often Nervous Before Their First Session — and Why They Do Not Need to Be

The anxiety patients bring into their first session almost always comes from one of three places. They have seen dramatic portrayals of hyperbaric chambers in movies or medical dramas. They have read something online that described a risk or side effect without any context. Or they simply do not know what to expect and uncertainty is uncomfortable for most people.

All of those are understandable. None of them reflect what a session at a properly run medical center actually feels like.

Hyperbaric oxygen therapy at our center is not dramatic. It is not loud. It is not painful. The vast majority of patients describe it as genuinely relaxing — an hour and a half where they lie still, breathe normally, watch television, and let the treatment do its work. Some patients fall asleep. That is how comfortable it is for most people.

The one sensation most patients do notice is ear pressure during the first few minutes as the chamber pressurizes. I am going to explain exactly what that feels like and exactly what to do about it. By the time you finish reading this article, that will not be a surprise either.

What Happens Before You Ever Get in the Chamber

Your first visit to RevitalizeMe is longer than a typical treatment session. We do not put anyone in a chamber on their first visit without taking the time to do this properly.

When you arrive, you will meet with our team for a comprehensive intake evaluation. We review your medical history, your current medications, your diagnosis, and the records from your referring physician or prior treatment. This is not a formality. We are looking for anything that affects your treatment plan or your safety, and we want to understand your full clinical picture before we prescribe a protocol.

After the clinical review, you will meet with our Safety Director for your hyperbaric orientation. This is one of the things that sets a properly run medical center apart. Our Safety Director goes through everything with you — what the chamber is, how it works, what you will experience during pressurization and depressurization, what you are and are not permitted to bring into the chamber, what to do if you feel uncomfortable at any point, and how to communicate with staff during your session.

This orientation is not rushed. We take the time to answer every question you have. If something is not clear, we go over it again. By the time you walk into the treatment room, nothing about the process should feel unfamiliar.

You will also be asked to change into 100 percent cotton attire before entering the treatment area. We provide this. Synthetic fabrics, certain lotions, perfumes, hair products, and personal electronic devices are not permitted in the chamber due to fire safety protocols in a high-oxygen environment. Your safety team will give you a complete list and make sure you are prepared.

Before your first session you will also go through a safety checklist with staff. This happens before every single session, not just the first one. It is part of how we operate.

What the Chamber Actually Looks and Feels Like

At RevitalizeMe we use Sechrist hard acrylic monoplace chambers. I want to describe these specifically because the image most people have of a hyperbaric chamber — a large metal cylinder with a small porthole window — is not what our patients experience.

Our chambers are made of clear acrylic. You can see in every direction. The chamber is well lit and you have a full view of the room and the staff around you throughout your session. There is no sense of being sealed into a metal tube in the dark. Patients who were certain they would feel claustrophobic are frequently surprised by how open the chamber feels once they are inside.

The chamber is large enough to lie comfortably. You are on a padded surface. There is a television mounted where you can watch it from inside the chamber. There is two-way communication so you can speak with staff at any point during your session and they can speak with you.

You are never locked in and unable to communicate. Staff are present and monitoring throughout every session. If at any point you are uncomfortable, you tell us and we respond.

I want to address claustrophobia specifically because it is the concern I hear most often from patients before their first session. The clear acrylic construction makes a significant difference for most patients who describe themselves as claustrophobic. The ability to see the room around you, see the staff, and communicate freely changes the experience considerably compared to what most people imagine. A meaningful number of patients who were genuinely worried about claustrophobia before their first session have gone on to complete full courses of treatment without issue.

That said, if claustrophobia is a significant concern for you, tell us before your first session. We can take additional steps during the orientation and the first pressurization to make the experience as comfortable as possible. We have managed this successfully with many patients. It is not a reason to avoid treatment without at least having a conversation with us first.

What Happens During Your Session — Minute by Minute

A standard hyperbaric oxygen therapy session at our center is approximately 90 minutes from the time you enter the chamber to the time you exit. Here is what that looks like.

The first 10 to 15 minutes — pressurization. Once you are settled in the chamber and the session begins, the chamber gradually pressurizes to the prescribed treatment pressure. This is the phase where most patients notice the ear sensation I mentioned earlier. It feels very similar to descending on an airplane or driving down a mountain. Your ears feel full or slightly pressured and you need to equalize them.

Equalizing is something your safety orientation covers in detail. The most common technique is swallowing, yawning, or gently pinching your nose and blowing softly — the same things you do on a plane. Most patients manage this easily after being shown how. Pressurization happens gradually so you have time to equalize comfortably as the pressure increases. If at any point the pressure feels too fast or uncomfortable, you communicate with staff and we slow down.

The middle 60 minutes — treatment at pressure. Once the chamber reaches the prescribed treatment pressure, you breathe 100 percent oxygen normally for approximately 60 minutes. This is the treatment phase. There is nothing you need to do during this time. Breathe normally. Watch television. Rest. Many patients use this time to simply decompress — no phone, no interruptions, just quiet time while the treatment works.

You may notice it feels slightly warm inside the chamber during pressurization. This is a normal physical property of gas compression and is temporary. Once the chamber reaches treatment pressure the temperature normalizes.

The final 10 to 15 minutes — depressurization. At the end of the treatment phase the chamber gradually returns to normal atmospheric pressure. This process is typically more comfortable than pressurization for most patients. You may notice a slight cooling sensation as the pressure decreases — again a normal physical property of gas expansion. Your ears may pop gently, similar to ascending on a plane.

When depressurization is complete the chamber opens and you exit. A staff member is present to assist you.

What You Will Feel Inside the Chamber

Beyond the ear equalization I described, most patients feel very little during a session that they would describe as uncomfortable.

What patients do frequently report is a sense of calm and relaxation during the treatment phase. You are lying still, breathing clean oxygen, with nothing demanding your attention. For many patients who are managing a serious wound or medical condition and carrying the stress that comes with that, this quiet time is genuinely restorative in a way they did not expect.

Some patients notice mild fatigue after their first few sessions. This is common and typically resolves as the body adjusts to treatment. It is not a sign that something is wrong. If you experience significant fatigue or anything that concerns you after a session, tell your care team at your next visit.

Occasionally patients experience mild sinus congestion or discomfort during pressurization, particularly if they have a cold or active sinus congestion on the day of treatment. This is one of the reasons we ask patients to let us know about any illness or congestion before a session. There are situations where it makes sense to reschedule a session rather than push through significant sinus discomfort.

Your care team reviews how you felt during and after every session. This is not a one-size-fits-all process. If something does not feel right, we want to know about it and we adjust accordingly.

What Happens After Your Session Ends

Most patients are able to drive themselves home after a hyperbaric oxygen therapy session and return to their normal daily activities. There are no restrictions on activity after a standard session for most patients.

Before you leave, a staff member will check in with you about how the session went. This brief post-session check is part of our standard protocol. We want to know how your ears felt, whether you experienced any discomfort, and how you are feeling overall. This information informs your ongoing treatment plan.

Your next session will be scheduled based on your prescribed treatment protocol. Most patients receiving HBOT for wound care or other covered indications come in for sessions five days a week. The number of total sessions varies depending on your diagnosis and your clinical response to treatment. Your physician will discuss the recommended protocol with you during your initial consultation and will reassess your progress throughout the course of treatment.

Between sessions, we ask patients to stay well hydrated, avoid alcohol on treatment days, and follow any specific instructions from their care team related to their underlying condition. If you have questions between sessions, call us. We would rather answer a question over the phone than have a patient sit at home uncertain about something.

How to Prepare for Your First Session — A Practical Checklist

Here is exactly what to do before your first hyperbaric oxygen therapy session at RevitalizeMe:

Before your first appointment:

• Bring all relevant medical records, imaging, and prior treatment notes. The more complete your record, the faster we can build an accurate picture of your situation.
• Bring your insurance card and a list of your current medications.
• Write down any questions you have. Your orientation appointment is the right time to ask everything.
• Let us know in advance if you have significant anxiety about enclosed spaces. We can take extra time during orientation to address this.
• Let us know if you have any active sinus congestion, ear pain, or upper respiratory illness. This may affect whether we proceed with the session that day.

On the day of your session:

• Eat a normal meal before your session. You do not need to fast.
• Stay well hydrated. Drink water before you come in.
• Do not apply lotions, perfumes, cologne, hairspray, or oil-based products before your session. These are not permitted in the chamber.
• Wear comfortable clothing to your appointment. You will change into 100 percent cotton attire provided by our center before entering the treatment area.
• Leave personal electronics, jewelry, and other items in your car or in our secure storage. These cannot go into the chamber.
• Arrive a few minutes early for your first session. The orientation takes time and we do not rush it.

What to tell us immediately:

• Any new medications started since your last visit
• Any illness, fever, or sinus congestion
• Any ear pain or difficulty equalizing during a previous session
• Anything that felt different or concerning after your last session

That is it. The preparation is straightforward. The session itself is manageable. And the team walking you through it has done this with a lot of patients who were nervous before they arrived and comfortable by the time they left.

FAQ: Your Questions About Your First HBOT Session Answered

Is hyperbaric oxygen therapy claustrophobic?

Our Sechrist hard acrylic monoplace chambers are fully transparent — you can see the room and staff around you in every direction throughout your session. Most patients who describe themselves as claustrophobic find the experience significantly more comfortable than they anticipated. If claustrophobia is a concern, tell us before your first session and we will take additional steps during orientation and pressurization to make you as comfortable as possible. It is not a reason to avoid treatment without first having a conversation with our team.

What should I wear to hyperbaric oxygen therapy?

You will change into 100 percent cotton attire provided by our center before your session. Do not apply lotions, perfumes, cologne, hairspray, or oil-based products on the day of your session. Synthetic fabrics and certain personal care products are not permitted in the chamber due to fire safety protocols. Your safety team will give you complete instructions during your orientation.

Can I watch TV during hyperbaric oxygen therapy?

Yes. There is a television visible from inside the chamber. Most patients watch television, rest, or simply relax during the 60-minute treatment phase. Personal electronic devices are not permitted inside the chamber but the in-room television is available throughout your session.

How long does a hyperbaric oxygen therapy session last?

A standard session at our center is approximately 90 minutes from the time you enter the chamber to the time you exit. This includes approximately 10 to 15 minutes of pressurization, 60 minutes at treatment pressure, and 10 to 15 minutes of depressurization. Your first visit will be longer overall due to the intake evaluation and safety orientation that occur before your first session.

Will I feel anything during hyperbaric oxygen therapy?

The most common sensation is ear fullness or pressure during pressurization, similar to descending on an airplane. This is managed with equalization techniques your safety team will teach you during orientation. During the treatment phase at pressure, most patients feel very little — many describe it as relaxing. Some patients notice mild fatigue after their first few sessions, which typically resolves as treatment continues. If you experience anything that concerns you during or after a session, tell your care team immediately.

— Dr. Cyrus Garmo, MD
Board-Certified Internal Medicine | Certified Hyperbaric Medicine, ATMO/UHMS
RevitalizeMe Hyperbaric Oxygen and Wound Care, Saginaw, MI
Individual results vary. This article is for informational purposes only and does not constitute medical advice. Please consult your physician regarding your individual care.