Oxygen Therapy Offers Promising Results in People With Crohn’s Fistulas
By
Updated on March 26, 2026
ON THIS PAGE
ON THIS PAGE
Hyperbaric oxygen therapy (HBOT), a treatment that increases oxygen levels in tissues to speed up the healing process, could be a safe and effective treatment option for people with fistulas — tunnel-like passages between two parts of the body that don’t normally connect — due to Crohn’s disease, according to a growing number of studies on the topic. Despite the preliminary research, randomized controlled trials are still needed to confirm its efficacy. And because of the lack of large-scale, high-quality studies, HBOT may not be covered by insurance.
For the treatment, people go into a special chamber that creates a pressurized environment filled with pure oxygen, which is intended to reach tissues to repair fistulas, which occur in up to 50 percent of people with Crohn’s over the course of their lives.
Read on to find out how HBOT works, what the research says, and what the drawbacks might be.
How Hyperbaric Oxygen Therapy Works
HBOT encourages new blood vessels to grow and decreases inflammation in tissues. Inflammation can deprive cells of oxygen (hypoxia), causing tissue to die. What’s more, research has shown hypoxia can induce inflammation — so it can become a vicious cycle.
“The decreased level of oxygen — hypoxia — and the development of inflammation are described to be two sides of the same coin; they can lead to each other,” says Sara Mesilhy, MBBS, a gastroenterologist with the Royal College of Physicians in England.
Because HBOT is effective in treating conditions related to hypoxia, doctors have found that the therapy may be beneficial as a therapy to complement other treatments for people with Crohn’s, a form of inflammatory bowel disease (IBD), who have difficult-to-treat and recurrent fistulas.
Hypoxia can contribute to inflammation in Crohn’s, which can then cause the formation of fistulas, small tunnels within the walls of the intestine that can connect to other organs or to the skin surface, causing pain and infection. The presence of fistulas means that inflammation has penetrated into adjacent organs, tissue, or skin.
“Hyperbaric oxygen therapy is a way to push oxygen into the colon through its tiny blood vessels,” said Parambir Dulai, MD, a gastroenterologist at Northwestern Medicine in Chicago. “This kills the inflammation-causing bad bacteria that thrive in these low-oxygen environments. It resets the immune system and allows the colon to heal,” he said.
What the Research Says About Hyperbaric Oxygen Therapy in Crohn’s
To get a more comprehensive view of the effectiveness of hyperbaric therapy on Crohn’s fistulas, Amr Dokmak, MD, the chief fellow in gastroenterology at the Brooklyn Hospital Center in New York City, and his collaborators reviewed 16 studies that included 164 Crohn’s patients with fistulas who underwent HBOT sessions.
Their analysis revealed that patients who received hyperbaric oxygen therapy had a clinical (symptom) remission rate of 59 percent. They also found a clinical response rate of 89, 84, and 29 percent for perianal (in or around the anus), enterocutaneous (between the intestine or stomach and the skin), and rectovaginal (rectum to vagina) fistulas, respectively.
“The response rate mentioned [in some research] is considered very impressive, making it a promising approach,” says Dr. Mesilhy. Advances have been made in IBD fistula healing through therapeutics such as biologics, and Mesilhy suggests that HBOT may prove to be an effective addition to the primary or initial therapy.
Other research has echoed these results. One paper noted that HBOT studies have shown improved healing, especially for complex fistulas in Crohn’s, and the researchers suggest the therapy can be offered along with other treatments for fistulas. And a small study of 11 people with Crohn’s and perianal fistulas found that about 55 percent achieved remission.
“The beneficial effects of hyperbaric oxygen therapy on inflammatory bowel disease activity may be not only due to increased oxygenation, but also to other changes the therapy makes as it adjusts the immune system by enhancing immune cells that protect the tissue, and enhances genes that produce intestinal barrier–protective elements,” says Mesilhy. “The exact long-term effects are still not known, as it varies from one patient to another — further studies are needed to evaluate the long-term effects.”
In addition to conducting more and larger randomized controlled studies to confirm HBOT’s efficacy for different types of fistulas, researchers must also figure out the best ways to treat people. The optimal number of HBOT sessions, for example, isn’t known, nor is which combination of surgeries, if needed, and medications work best with HBOT.
Treatment Can Be Pricey
Modern HBOT has existed since the 1930s, when it was used to treat U.S. Navy divers who had decompression sickness, also known as “the bends,” which occurs when excess nitrogen in the bloodstream and a too-fast ascent to the water’s surface leads gas bubbles to block blood vessels. Since that time, the therapy has been used to treat carbon monoxide poisoning, gangrene, wounds that won't heal, and infections in which tissues are starved for oxygen.
HBOT requires a series of treatments to be effective; it's not a one-time treatment. One of the major drawbacks of the treatment is its high cost and lack of universal insurance coverage, due to the fact that more studies are needed to prove its effectiveness, according to research.
The Takeaway
- Preliminary research indicates that hyperbaric oxygen therapy (HBOT) is effective for treating Crohn’s disease–related fistulas, tunnel-like passages between two parts of the body that don’t normally connect.
- Up to 50 percent of people with Crohn’s will develop a fistula in their lifetime, and research indicates that HBOT may be an effective complementary treatment, along with medication and surgery, if needed.
- More studies are needed to prove the therapy’s effectiveness and determine treatment protocols; as a result, it’s not currently covered by most insurance for fistulas, and the cost can be considerable.
EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
- Dokmak A et al. Efficacy and Safety of Hyperbaric Oxygen Therapy in Fistulizing Crohn’s Disease: A Systematic Review and Meta-Analysis. Journal of Clinical Gastroenterology. February 2024.
- McNamara J et al. Epidemiology and Treatment Patterns of Fistulizing Crohn’s Disease in a Large, Real-World Australasian Cohort. Gastro Hep Advances. November 28, 2024.
- Fu Q et al. Hyperbaric Oxygen Therapy for Healthy Aging: From Mechanisms to Therapeutics. Redox Biology. July 2022.
- Rivers RJ et al. The Tissue Response to Hypoxia: How Therapeutic Carbon Dioxide Moves the Response Toward Homeostasis and Away From Instability. International Journal of Molecular Sciences. March 7, 2023.
- Saas P et al. Editorial: Hypoxia and Inflammation: A Two-Way Street. Frontiers in Immunology. March 7, 2023.
- Hyperbaric Oxygen Therapy. Cleveland Clinic. January 7, 2023.
- McGregor CGC et al. Pathogenesis of Fistulating Crohn’s Disease: A Review. Cellular and Molecular Gastroenterology and Hepatology. September 29, 2022.
- Fistulas. Crohn’s & Colitis UK. January 2026.
- Hyperbaric Oxygen Therapy Helps Hospitalized Patients With Ulcerative Colitis. Northwestern Medicine. May 19, 2022.
- Wetwittayakhlang P et al. The Optimal Management of Fistulizing Crohn’s Disease: Evidence Beyond Randomized Clinical Trials. Journal of Clinical Medicine. May 27, 2022.
- Kaur H et al. Role of Hyperbaric Oxygen Therapy in Patients With Inflammatory Bowel Disease. Current Opinion in Gastroenterology. July 2023.
- Piotrowicz G et al. Impact of Hyperbaric Oxygen Therapy on Perianal Fistulas in Crohn’s Disease: Clinical Outcomes and Remission Rates. Journal of Crohn’s and Colitis. January 22, 2025.
- Saracino M. A Deep Dive Into Decompression Sickness: Advancements in Hyperbaric Oxygen Therapy for Navy Divers. National Museum of Health and Medicine. November 14, 2024.
- Hyperbaric Oxygen Therapy. Johns Hopkins Medicine.
- Alenazi N et al. A Review of Hyperbaric Oxygen Therapy for Inflammatory Bowel Disease. International Journal of General Medicine. October 24, 2021.
- Tome J et al. Hyperbaric Oxygen Therapy for Refractory Perianal Crohn’s Disease: A Case Report. Gasteoenterology & Hepatology. April 2024.
Meet Our Experts
Ira Daniel Breite, MD
Medical Reviewer
Ira Daniel Breite, MD, is a board-certified internist and gastroenterologist. He is an associate professor at the Icahn School of Medicine at Mount Sinai, where he also sees patien...
Don Rauf
Author
Don Rauf has been a freelance health writer for over 12 years and his writing has been featured in HealthDay, CBS News, WebMD, U.S. News & World Report, Mental Floss, United Press ...