hyperbaric oxygen therapy side effects and what your first session is like

When people ask me about hyperbaric oxygen therapy side effects, my first answer is short. Complications are uncommon, and the one reported most often is ear discomfort as the pressure changes. Harvard Health notes that complications of hyperbaric oxygen therapy are uncommon, but they can occur, and a systematic review and meta-analysis of hyperbaric trials found ear discomfort to be the most frequent side effect.

I am Dr. Alireza Chizari, DC, DACNB, a Board-Certified Functional Neurologist, and I supervise hyperbaric oxygen therapy at California Brain & Spine Center in Calabasas. If you are thinking about a first session, you are probably carrying two questions at once: is it safe for me, and what does an hour in the chamber actually feel like?

Below are the side effects published sources describe, how pressure and screening shape them, who is usually asked to wait, and a plain walk-through of a first session in the practice's two hard-shell chambers.

What Are the Common Hyperbaric Oxygen Therapy Side Effects?

Hyperbaric oxygen therapy is a treatment in which you sit or lie in a special chamber while the pressure around you is raised above normal air pressure, and the oxygen level in your blood rises. Each side effect below connects to some part of that experience: the pressure change, the oxygen, or simply spending an hour in an enclosed space.

Pressure, the Ears and the Sinuses

As the pressure changes, Cleveland Clinic explains, your ears may feel clogged or start to pop, much like flying in an airplane or driving through mountains. University of Iowa Health Care describes ear barotrauma, a pressure injury to the ear, as the most frequent complication of hyperbaric oxygen.

The sinuses follow the same physics in smaller spaces. When they cannot equalize with the pressure in the chamber, the result can be significant sinus pain, often called a sinus squeeze. That is one reason a session pauses for nothing more dramatic than you raising a hand and saying your ears or sinuses hurt.

The Rarer Effects Worth Knowing About

Harvard Health lists the complications that are uncommon but possible: ear and sinus pain, rupture of the eardrum, temporary vision changes and, rarely, lung collapse. The vision change has a specific mechanism. According to University of Iowa Health Care, hyperbaric oxygen can temporarily change the shape of the lens in the eye, which can change how clearly you see during a course of treatment.

The rarest concern is the oxygen itself. The high level of oxygen in the blood during treatment can be toxic to the central nervous system, and that is the reason behind the rare risk of seizures. At the practice, screening comes first for everyone, and pressure, session count and frequency are set for each person.

Do Hyperbaric Oxygen Therapy Side Effects Depend on Pressure?

In a pooled analysis of trials, hyperbaric oxygen therapy side effects were reported more often at higher chamber pressures and over longer courses of treatment. That meta-analysis in Frontiers in Medicine also found ear discomfort to be the most frequent side effect across the trials it reviewed.

Both chambers at California Brain & Spine Center are hard-shell units in which you lie on your back. The original chamber and the newer, larger one each work within their own pressure range, and the setting used for you is chosen after screening. Neither is a soft chamber.

Lower pressure does not mean no side effects. Your ears can still feel the change at any setting, and the same screening applies to everyone. What the pooled analysis gives is a reason to take pressure and course length seriously, and here both are decided person by person after screening rather than taken from a standard protocol.

What Happens at Your First Hyperbaric Oxygen Therapy Session?

A first hyperbaric oxygen therapy session at the practice starts with screening, then about an hour lying in a hard-shell chamber, with the session run by trained clinic staff under Dr. Chizari's supervision. In order, it looks like this.

1. Before anything else, you are screened: your health history, lung history, any pregnancy, diabetes and how you feel in enclosed spaces.
2. From what screening finds, your pressure, number of sessions and frequency are set individually. There is no single standard course.
3. You lie down on your back in the chamber, and only what the staff have cleared goes in with you, because high concentrations of oxygen carry a fire risk, as Harvard Health points out.
4. As the pressure builds, your ears may feel full or pop; you clear them as it rises, and you tell the staff straight away if your ears or sinuses hurt.
5. The session itself lasts about an hour, with staff nearby throughout.
6. Afterward, Cleveland Clinic notes, you may feel sleepy, so a quiet stretch after your first sessions is sensible.

How Might Each Side Effect Feel, and What Should You Tell Staff?

Most hyperbaric oxygen side effects feel like ear fullness or popping, sinus pain, a change in vision or sleepiness, and during a session you tell staff at once about any of them. The table below sets out what each may feel like and what to do, during the session or at screening beforehand.

Who Should Not Have Hyperbaric Oxygen Therapy?

An untreated collapsed lung (pneumothorax) is the one condition considered an absolute contraindication (a reason not to have treatment at all) to hyperbaric oxygen therapy, according to StatPearls on the NCBI Bookshelf. Other conditions are relative contraindications, weighed person by person during screening.

Cleveland Clinic names a collapsed lung, certain lung diseases such as COPD, and pregnancy among the situations in which a person may not be a candidate. That is why the screening questions reach well beyond the reason you came in, and why it helps to raise these points yourself:

• If you have diabetes, say so, because some people with diabetes experience a drop in blood sugar during hyperbaric treatment.
• If enclosed spaces bother you, mention it early: some people feel claustrophobic in the chamber, and people who already are may find it harder.
• Any lung history, including COPD or a past collapsed lung, belongs on the screening form, along with a pregnancy.

Can Hyperbaric Oxygen Help After a Concussion or With Brain Fog?

For some neurological patients, hyperbaric oxygen may be considered as an adjunct, meaning one addition to their care, for selected people after screening. I do not present it as a proven treatment for any of these problems.

The people it may be considered for include those with persistent post-concussion symptoms, brain fog or cognitive fatigue, neurological fatigue, and selected post-COVID presentations. Whether it has a place alongside concussion care in Calabasas is decided after an evaluation, never assumed.

The practice also offers hyperbaric-only programs and multi-session packages, with no rehabilitation program required. If foggy thinking is your main concern, the page on brain fog treatment describes how that symptom is looked at as a whole.

Hyperbaric oxygen therapy is not FDA cleared or approved for conditions such as Alzheimer's disease, autism, cancer and Lyme disease, as Harvard Health points out, and it is not offered here for them.

What Do Patients in Calabasas Ask Before a First Session?

Patients in Calabasas and Agoura Hills often ask me whether the pressure hurts, what can go into the chamber, and why screening asks about diabetes or their lungs.

One question patients often ask me is whether the pressure is going to hurt their ears. My honest answer is that the ears may feel clogged or pop as pressure changes, much as on a flight, and that you tell the staff the moment it is uncomfortable. Your pressure is set for you after screening, within the range of the chamber you use.

Another is what they can bring in with them. Because high concentrations of oxygen carry a fire risk, only what the staff clear goes into the chamber. The width of the screening surprises people too, and the reason sits in the contraindications above: lung history, pregnancy and diabetes all change whether and how a session is planned.

At California Brain & Spine Center in Calabasas, Dr. Alireza Chizari, DC, DACNB, a Board-Certified Functional Neurologist whose field is functional neurology, supervises every hyperbaric session, and the chamber, the pressure plan and the reason behind each screening question are explained before a first session is booked.

"Dr. Chizari took the time to explain everything clearly and made the whole process easy to understand."

From a Google review

Hyperbaric Oxygen Therapy Side Effects: Short Answers

Hyperbaric oxygen therapy side effects raise a handful of shorter questions before a first session, and these are the ones answered in a few sentences each.

The short version of hyperbaric oxygen therapy side effects is the one I started with. Complications are uncommon, ear pressure is the one people notice, and screening decides who goes ahead and at what pressure. If you are weighing a first session, I would rather you arrive with your questions written down than sit on them. You can reach the practice at California Brain & Spine Center | (818) 649-5300 | Calabasas, CA 91302, or book online.

This content is for educational purposes only and is not medical advice. Consult a qualified healthcare provider about your specific situation.