Role of Hyperbaric Oxygen Therapy (HBOT) in Mold Sickness exposure and management

What is Mold Sickness?

Molds are fungi that can grow inside or outside. They flourish in hot, wet, and humid climates. Mold is incredibly diverse and releases spores, allowing them to disperse and multiply. The rapid growth of mold in moist environments can cause extensive damage to building materials like drywall, carpet padding, and subflooring. If there is excessive mold growth, a building’s structure can be damaged. Mold growth areas are not only home to the mold itself but also bacteria, dust mites, the byproducts of bacterial and mold decay. Moreover, the chemicals, gases, and particulate matter that are released into the air as a byproduct of mold growth are also present in moldy area.

The World Health Organization (WHO) reported in 2009 that anywhere from 10 to 50 percent of buildings have mold problems severe enough to warrant medical attention. The percentage rises to 30–50% in recently constructed or renovated structures. Constructing buildings with less energy has its advantages, such as lower electricity bills, but the enclosed, humid conditions are a breeding ground for mold and other health problems [1].

Various kinds of mold

According to a recent study, one out of every 1,000 homes in the United States has mold. Scientists place these molds into different categories depending on how they affect living things.

Mold allergens

Molds that cause allergies are relatively harmless. Asthmatics and those with a preexisting allergy to that particular mold are the only people who are susceptible to allergy. Mold allergies affect more children than adults.

Pathogenic molds

Molds that spread disease are called pathogenic molds. Those with weak immune systems face a severe threat from this. It is common for people exposed to these molds to experience an acute reaction similar to bacterial pneumonia.

Toxigenic molds

These molds produce mycotoxins, and as the name suggests, they can devastate human health. Studies have found that they suppress the immune system and may even cause cancer. Inhaling, ingesting, or touching these molds can all result in the absorption of their toxic chemicals into the body.

Indoor mold

Mold exposure can cause a wide range of health issues, collectively known as “mold illness.” Although mold allergies are the most common reaction to mold exposure, mold can still cause illness, even in those who do not have allergies. Toxic mold can cause allergic reactions, asthma, and other respiratory problems. Mold infections can cause many symptoms and complications, from the common cold and cough to a rash and even pneumonia.

Chronic Inflammatory Response

Furthermore, mold toxicity is a problem that causes a chronic inflammatory response. Toxic organisms found inside a water-damaged building, such as fungi, bacteria, actinomycetes, and Mycobacterium, can trigger a systemic inflammatory response that can be acute and chronic. Inflammogens maintain an inflammatory response in the body [2].

Underlying mechanism of Mold Sickness due to mycotoxicity

Toxic mold spores and fungal fragments contain substances called mycotoxins. Mycotoxins like these are easily dispersed through the air after being released. There are multiple routes of entry for mycotoxins into the body: inhalation, skin contact, and ingestion of moldy foods. 

Mycotoxins are toxic to humans because they cause the release of inflammatory cytokines. In immune function, cytokines play a crucial role in cell signaling and facilitate cell-to-cell interaction during immune function. In addition, they encourage cell migration to sites of injury, infection, or inflammatory processes.

Chronic Inflammatory Response Syndrome or Mold Sickness

Chronic Inflammatory Response Syndrome (CIRS) is known as “mold sickness”. Exposure to water in a damaged building can cause this illness. The meaning of “significant exposure” may vary from person to person. Even a brief exposure can cause serious harm to some people. Furthermore, even low doses accumulate and cause harm. These people may have an adverse response when exposed to the antigen for the second time.

Symptoms of CIRS

It’s vital to keep in mind that mold sickness is an actual medical condition, not just an allergy. Quite a few different symptoms are associated with this condition. Some more apparent signs of mold exposure are respiratory problems, sneezing, runny nose, and skin problems. Memory and concentration problems, among other symptoms, tend to worsen with prolonged exposure to water-damaged buildings and mold.

Some people seem to get sicker than others, but why is that?

Some people have better detoxification capabilities than others when exposed to toxins in water-damaged buildings. When exposed to mold for the first time, the body recognizes it as an antigen and produces antibodies to fight it off. About a quarter of the population, however, carries the HLA-DR gene and is, therefore, predisposed to mold allergies. Their bodies’ natural defenses against antigens, or foreign substances, are insufficient to eliminate the fungus. While many people get sick from being in water-damaged buildings with mold, most recover once, they are no longer susceptible to the spores. The toxic substances cause a persistent systemic inflammatory response in the 25% of the population who carry the HLA-DR gene. The victims of mold sicknesses also known as CIRS patients[3].

Hyperbaric Oxygen Therapy for Mold Sickness

Hyperbaric oxygen therapy (HBOT) can be helpful in the treatment of mold sickness. To alleviate mold toxicity, HBOT is effective in treating symptoms like fatigue, cognitive impairment, and headaches. The number of HBOT treatments needed to achieve optimal results varies from patient to patient but is typically between 30 and 60. Furthermore, the number of treatments a person requires may vary depending on the severity of their symptoms [4].

Management of Mold Sickness with Hyperbaric Oxygen Therapy 

According to Dartmouth’s Geisel School of Medicine’s Robert Cramer, Ph.D., treating patients in a hyperbaric chamber with extremely high oxygen concentrations inhibits the fungus’ progress. High oxygen content aids the body’s natural detoxification processes, eliminating mold toxins from cells and tissues easier.

HBOT strengthens the immune system by providing the body with more oxygen than usual. As a result, the body can better defend itself against harmful bacteria and viruses. In instances where mold may have hurt brain function, such as memory problems, the extra oxygen helps the brain to recover. This often resolves memory and other cognitive issues. On top of that, mold causes inflammation in the human body. HBOT decreases inflammation by enhancing anti-inflammatory cytokines and speeding up fibroblast stimulation [5].

Studies on the effect of HBOT on mold toxicity

Numerous studies examine the effects of hyperbaric oxygen therapy on mold exposure, toxicity, and infections. The American Society for Microbiology studied hyperbaric oxygen’s effect on Aspergillus fumigatus growth. This study examined how hyperbaric oxygen affected A. fumigatus in vivo and in vitro. While many mold and fungal infections respond well to antifungals, A. fumigatus infections are fatal. The disease may cause low oxygen levels at the infection site and hinders antifungal drugs. The study found that HBOT at 3.5 ATA reduced A. fumigatus growth by 50 percent [6].

The traditional treatments for invasive aspergillosis are amphotericin B and surgery. This treatment had an unacceptable death rate. In a 2002 study, ten patients, most with hematologic malignancies and rhinosinusitis, received HBOT and traditional care. Six of 10 patients were infection-free after the first treatment. They concluded that HBOT is effective in treating this disease [7].

HBOT improves attention span disruption caused by mold toxicity

A 2011 study examined the effects of hyperbaric oxygen on mold-toxic patients’ attention spans and reaction times. Mold and mycotoxins can impair short-term memory, disorientation, balance and coordination, attention span, and reaction time in adults and children. This study included 15 people ranging in age from 18 to 58. Researchers found mold and mycotoxins in all patients. All the exposed participants got sick. All 15 patients developed clinical attention deficit syndrome after exposure, disrupting their attention span and reaction time. All 15 patients showed improved attention and reaction time after 10 HBOT sessions [8]. 


Molds, which are fungi, may colonize both inside and outdoors. Allergies, asthma, and other respiratory issues are just some of the issues that mold may bring on. Mold sickness can cause a wide range of symptoms and complications, from the common cold and cough to a rash and pneumonia. This disease can be contracted by being in a water-damaged building. For severe mold sickness, hyperbaric oxygen therapy (HBOT) may be the best option. Mold poisons are more easily flushed out of cells and tissues when there is more oxygen available to the body.

Symptoms including tiredness, brain fog, and headaches respond well to HBOT. Toxic mold exposure, mold infections, and the efficacy of hyperbaric oxygen therapy are the subjects of research. Short-term memory, disorientation, balance and coordination, attention span, and response speed can all be negatively impacted by mold and mycotoxins in both adults and children. Hyperbaric oxygen therapy reduces the interruption of attention span brought on by mold poisoning. 



  1. “Mold Exposure Mold Toxicity – National Hyperbaric.” Mold Exposure Mold Toxicity – National Hyperbaric, www.nationalhyperbaric.com/hbot-treatments-and-conditions/mold-exposure-mold-toxicity 
  2. Neil-Sherwood, Dr. Michele. “11 Signs of Mold Illness.” Functional Medical Institute, 30 May 2017, https://fmidr.com/mold-illness/ 
  3. “What You Should Know About Mold Illness (CIRS) — Genesis Performance Chiropractic of Elverson, PA.” Genesis Performance Chiropractic of Elverson, PA, 5 May 2020, www.genesisperformancechiro.com/blog/2020/4/27/why-you-should-know-about-mold-mycotoxins-and-mold-illness-cirs 
  4. Osgood, Dr. Seth. “How Can Hyperbaric Oxygen Help With Mold Toxicity?” GrassRoots Functional Medicine, 12 Oct. 2022, https://grassrootsfunctionalmedicine.com/blog/hbot-for-mold-toxicity/
  5. Durgin, Jennifer. “Investigating the Deadly Potential of a Common Fungus.” Geisel News, 8 Sept. 2014, https://geiselmed.dartmouth.edu/news/2014/investigating-the-deadly-potential-of-a-common-fungus/   
  6. Dhingra, Sourabh, et al. “Hyperbaric Oxygen Reduces Aspergillus Fumigatus Proliferation in Vitro and Influences in Vivo Disease Outcomes.” Antimicrobial Agents and Chemotherapy, vol. 62, no. 3, American Society for Microbiology, Mar. 2018. Crossref, https://doi.org/10.1128/aac.01953-17.
  7. García-Covarrubias, Lisardo et al. “Invasive aspergillosis treated with adjunctive hyperbaric oxygenation: a retrospective clinical series at a single institution.” Southern medical journal vol. 95,4 (2002): 450-6. https://pubmed.ncbi.nlm.nih.gov/11958246/ 
  8. Ezra, N., et al. “Improvement of Attention Span and Reaction Time With Hyperbaric Oxygen Treatment in Patients With Toxic Injury Due to Mold Exposure.” PubMed Central (PMC), 27 Oct. 2010, www.ncbi.nlm.nih.gov/pmc/articles/PMC2998645


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