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Ozone Therapy

Tom Escott
— By Tom Escott on March 20, 2024

Ozone is a gas that was discovered in the mid-nineteenth century. Its molecular structure consists of three atoms of oxygen, which makes it denser and more soluble in water [1]. Ozone is present in low levels in the atmosphere and provides protection from ultraviolet radiation [1]. It is highly unstable and rapidly breaks down into oxygen plus a single reactive oxygen atom [1]. If inhaled it can damage the respiratory system and cause inflammation in the airways [2].

Ozone therapy has been used as a medical treatment since the the mid-nineteenth century. Its molecular structure consists of three atoms of pure oxygen, which makes it 10x more active than regular oxygen.

Ozone therapy is an integral feature of some comprehensive cancer protocols.  It improves the action of other anti-cancer therapies, has a direct anti-cancer action, and protects the immune system and other side effects that are common with chemotherapy and radiation therapy.

Ozone is present in low levels in the atmosphere and provides protection from ultraviolet radiation [1]. It is highly unstable and rapidly breaks down into oxygen plus a single reactive oxygen atom [1]. If inhaled it can damage the respiratory system and cause inflammation in the airways [2].

Ozone is produced by specialized generators and immediately used for therapeutic purposes. Its effects have proven to be consistent and safe with minimal side effects for a range of different pathologies [3] [4]. Medical ozone is used for disinfection and treating a wide variety of diseases. It has been shown to inactivate bacteria, viruses, fungi, yeast, and protozoa, stimulate oxygen metabolism, and activate the immune system [3]. It has been shown to inactivate bacteria, viruses, fungi, yeast, and protozoa, stimulate oxygen metabolism, and activate the immune system [3]. Ozone therapy may involve body saunas, insufflation into body cavities (not the lungs), topical application to joints and lesions, wound care, and mixing with a patient’s own blood and then re-infusing (known as autohemotherapy) [1].

Ozone therapy for cancer (most commonly autohemotherapy) delivers ozone into the body with the aim of increasing oxygen levels and killing cancer cells [2]. It is claimed that ozone therapy can reverse hypoxic (low-oxygen) conditions that are required from the growth of cancer cells and development of tumors [1]. By increasing oxygen levels, ozone is believed to adversely affect cancer cells and cause apoptosis (programmed cell death) without damaging healthy cells [1] [5]. It has also been shown to be a powerful antioxidant, which may provide therapeutic effects against cancer [1].

Ozone may also help to reduce the side effects and improve outcomes of standard of care treatments such as radiation and chemotherapy [6].** **Over several decades, prestigious scientific journals have published research on the anticancer effects of ozone as well as its ability to enhance the effects of radiotherapy and chemotherapy [7]. Unfortunately, there are currently only a handful of clinical studies on ozone therapy for the treatment of cancer in humans. Preclinical research (laboratory and animal studies) indicates a potential role for ozone in cancer care [7]. However, randomized clinical trials in humans are still required to confirm its therapeutic safety and efficacy.

History of Ozone Therapy

The history of ozone’s discovery is linked with the evolution of some of the earliest concepts in chemistry [8]. In 1785, Martinus Van Marum, subjected oxygen to an electrical current and noted what he referred to as “the odor of electrical matter” [8]. In 1840, Christian Friedrich Schonbein, a professor of Chemistry at the University of Basel in 1840, repeating the same experiments, came to the conclusion that the distinct smell was due to a gas that he called ‘ozone’ [1] [8]. The term is derived from the Greek word ‘ozein’ meaning ‘odorant’ and the chemical formula was determined in 1865 [1] [8].

Soon after the discovery of ozone the scientific community began to realize that ozone was more than just another gas of the Earth’s atmosphere [4]. The first therapeutic application of ozone can be traced back to 1870 when C. Lender used it for the purpose of purifying blood in test tubes [6]. From that point onwards the use of ozone has been explored for the treatment of infections, wounds, and multiple diseases [3].

A major revolution in ozone therapy occurred in the early 1900s after the development of highly specialized ozonators, which could produce precise and pure mixtures of oxygen and ozone [6]. The first ozone generator was patented by the genius inventor Nikola Tesla in 1896. He later formed the ‘Tesla Ozone Company’ [3]. A critical aspect in the advancement and efficacy of ozone therapy was the identification of inert elements that could withstand ozone’s oxidative properties such as teflon, polyvinyl fluoride, silicone, and gold [6].

In 1901, Nice in France and Wiesbaden in Germany became the first cities to use ozonation to purify their drinking water, soon followed by Zurich, Florence, Brussels, Marseille, Singapore, and Moscow [8]. Today there are thousands of cities across the world that use ozone for this purpose [8].

During the First World War (1914-1918), aware of ozone’s antibacterial properties, doctors with few other medical resources available used it to treat infected wounds and burns in soldiers [3] [6]. They discovered that ozone not only remedied the infections, but also improved blood flow to tissues, and had anti-inflammatory properties [3].

In the 1970s, Dr. Velio Bocci, an Italian professor of physiology, began what would turn into decades of research into the therapeutic effects of ozone on the human body, which was primarily published in the 1990s and 2000s [5]. His research found that ozone could stimulate the immune system, increase oxygen delivery to tissues, and have potent anti-inflammatory effects [5]. His findings sparked the use of ozone for a variety of medical purposes, including in cancer care.

Research on Ozone Therapy for Cancer

Over several decades of scientific research into ozone therapy for cancer, multiple prestigious journals have published in vitro (laboratory) and in vivo (animal) studies that show ozone can destroy cancer cells, and enhance the effects of conventional treatments [7]. However, there are very few clinical studies on ozone therapy for cancer in humans to determine if the preclinical research translates into therapeutic benefits for cancer patients.

A 2018 review of the research on ozone therapy for cancer concludes that in vitro and in vivo studies_,_ as well as_ _a few isolated clinical reports in humans, indicate that ozone has a potential role as an adjuvant (supportive) therapy to enhance the anticancer effects of radiotherapy and chemotherapy, while also reducing their damaging side effects [7]. The review explains that ozone can induce direct damage on tumor cells, modulate the immune system, and increase the anticancer effects of radiation and chemotherapy. Furthermore, it can modify blood flow and tumor hypoxia (low oxygen levels), which could provide additional therapeutic benefits during cancer treatment.

Similarly, a 2019 review on ozone therapy and cancer highlights strong evidence that ozone therapy reduces tumor hypoxemia (low oxygen in blood), which in turn allows for greater efficacy of radiotherapy and/or chemotherapy [6]. Furthermore, the review highlights the fact that chemotherapy and radiation can have potentially fatal side effects and reduce quality of life. The authors explain that ozone could play a potential role in reducing side effects and improving outcomes for cancer patients.

A 2018 study on 50 patients with various types of cancer and fatigue were treated with ozone therapy twice a week for one month and then twice monthly as maintenance therapy [10]. No side effects were reported and 75% of the patients reported a significant reduction in fatigue. The researchers indicate that ozone could be a valid supportive therapy to reduce symptoms of fatigue during cancer treatment and in palliative care.

In 2012, a report was published on 40 patients with advanced non-small cell lung cancer who were treated with ozone therapy (autohemotherapy) in conjunction with mistletoe [11]. Results showed a significantly increased quality of life score compared to the control group. In 1998, a study in Cuba on 70 patients with prostate cancer showed that radiotherapy combined with ozone therapy resulted in greater and quicker reductions in PSA levels compared to radiotherapy alone [9].

The journal Nature has been publishing research on the effects of ozone since the late 1950s. The first publication in 1958 reported that ozone gas can have similar effects to radiation [12]. In 1980 another prestigious journal, Science, published research showing that ozone could selectively inhibit the growth of various human cancer cells including breast, lung, and uterine [13]. Over the years, numerous preclinical studies have shown that ozone can have both direct anticancer effects and indirect anticancer effects via stimulation of the immune system [9] [14] [15] [16] [17]. However, there is currently very limited clinical research to confirm the efficacy of ozone therapy as a cancer treatment for humans.

Potential Applications of Ozone Therapy

Ozone therapy has been shown to have potential therapeutic application for a range of different disorders and diseases [4]. Numerous laboratory studies have provided evidence that ozone has potent antioxidant properties as well as the capacity to modulate the immune, vascular, and hematologic systems [4].

There is evidence to suggest that ozone therapy may provide certain benefits in the treatment of the following pathologies [1] [4]:

  • Cardiovascular
  • Neurological
  • Circulatory
  • Gastrointestinal
  • Orthopedic
  • Wounds
  • Skin lesions
  • Diabetes
  • Infections
  • Rheumatic diseases
  • Parkinson’s disease
  • Macular degeneration
  • AIDS

There is reasonable scientific evidence and clinical justification that ozone therapy could be applied as an adjuvant for the management and prevention of cancer treatment-related toxicity [7]. Ozone has shown great potential in amplifying the administration of radiotherapy and chemotherapy in patients who otherwise may not be suitable candidates due to poor overall health [7]. This could include patients with poor kidney, liver, lung, or heart function, or in situations where treatment comes with a high risk of toxicity [7].

Many reports have highlighted that the systemic use of ozone therapy may help to enhance the effects of radiotherapy and chemotherapy [7]. The method of administration of ozone therapy that is most commonly related to cancer treatment is autohemotherapy [1]. It involves drawing blood from the patient’s vein, which is then treated with ozone before re-infusion into a vein or muscle [1]. Furthermore, promising preclinical results have been published on the intraperitoneal use of ozone [7]. However, more research needs to be conducted to determine if ozone has direct clinical application in the treatment of cancer.

In 1931, Dr. Otto Warburg received the Nobel Prize in physiology for his discovery of the nature and mode of action of the respiratory enzyme in tumor cells [6]. He came to the conclusion that the main cause of malignant growth is oxygen deprivation, which leads to anaerobic respiration (glycolysis /fermentation) in cancer cells [6].

It is theorized (but not yet clinically proven) that ozone may have direct anticancer effects related to the disruption of glycolysis in tumors. The purported mechanism of action is based on the concept that increasing oxygen levels in the vicinity of cancer cells will damage them and potentially trigger apoptosis (programmed cell death) [1]. It is claimed that ozone can reverse local hypoxic conditions that can support cancer development and growth [1]. However, the relationship between oxygen and cancer cells is highly complex and levels of hypoxia can vary greatly in malignant tumors [1].

It has also been suggested that the reported therapeutic effects of ozone therapy may be due to controlled and moderate oxidative stress produced by the ozone reacting with compounds in the body [1]. Moderate and controlled oxidative stress can trigger the production of antioxidant enzymes, which can help to protect cells from oxidation, inflammation, and may even reverse chronic oxidative stress [1].

In clinical practice, ozone does not generally enter into direct contact with tumor cells, which means, in most cases, it does not exert a direct anticancer effect [7]. The benefits of the therapy for cancer treatment are therefore more likely to be related to an indirect mechanism of action that modulates and activates the immune system, increases circulation, oxygenates the blood, and reduces oxidative stress [7].

Oxidative stress has been shown to play a major role in cancer hallmarks such as chronic inflammation, angiogenesis (formation of new blood vessels), invasiveness (ability to penetrate surrounding tissues), stemness (self-renewal and generation), and metastatic ability (capacity to spread) [18]. Therefore, reducing oxidative stress can be a supportive therapeutic strategy in cancer care.

Risks and Side Effects of Ozone Therapy

Much of the scientific research on the safety of ozone has been related to its effect in the atmosphere. Large scale studies have shown that an increased exposure to ozone is linked to an increased risk of death from respiratory diseases [1]. It is considered to be an air pollutant that can negatively affect the respiratory system, reduce lung function, and cause inflammation in the airways when inhaled [2]. One of the major contraindications of ozone therapy is inhalation into the lungs, which can cause adverse effects [4].

With regard to the therapeutic application of ozone there is a lack of high quality research to evaluate safety [1]. However, a 2016 review of the clinical data available on ozone use in medicine found that ozone treatments in the form of Major Ozone Autohemotherapy (MAH) and Rectal Insufflations (RI) were safe [19]. The study included over 11,000 MAH treatments in 577 patients and over 47,000 RI treatments in 716 patients without any reported side effects or adverse events.

There is currently little reliable safety information on other methods of ozone administration [2]. Certain circumstances where ozone therapy may be harmful include [2]:

  • Hyperthyroidism
  • Leukemia
  • Advanced stages of HIV
  • Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency
  • Injection into the arteries
  • Hyperbaric medical ozone infusions

There is currently not enough evidence to determine if ozone therapy would be safe for people who are pregnant or nursing [2]. Direct infusion of ozone intravenously has resulted in pulmonary embolism and death [1]. This mode of administration has been prohibited in certain countries and is generally contraindicated [1].

The safety profile and risk of toxic effects with ozone therapy depends greatly on the concentration of ozone applied, mode of application, and administration to appropriate sites [4]. Ozone therapy appears to be safe in the form of MAH and RI [1]. However, there is limited safety information available. Further research is still needed.

Frequently asked questions about Ozone Therapy

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The Best 134 Integrative Cancer Treatment Centers that offer Ozone Therapy

References of Ozone Therapy

[1] Karen Pilkington. (2020). Ozone therapy. CAM Cancer Consortium.

[2] Beth Sissons. (2022). Is ozone therapy a viable treatment option for breast cancer?. Medical News Today. ]([

[3] Elvis, A. M., & Ekta, J. S. (2011). Ozone therapy: A clinical rev_iew. Journal of natural science, biology, and med_ic_i_ne, 2(1), 66–70.

[4] Smith, N. L., Wilson, A. L., Gandhi, J., Vatsia, S., & Khan, S. A. (2017). Ozone therapy: an overview of pharmacodynamics, current research, and clinical util_ity. Medical gas res_ea_r_ch, 7(3), 212–219.

[5] Bocci V. A. (2006). Scientific and medical aspects of ozone therapy. State of the art. Archives of medical research, 37(4), 425–435.

[6] Singh, V., Rishabh, G., & Sandeep, K. (2019). Role of ozone therapy and cancer: myth or real_ity._ JM_S_CR, 7, 720-727.

[7] Clavo, B., Santana-Rodríguez, N., Llontop, P., Gutiérrez, D., Suárez, G., López, L., ... & Rodríguez-Esparragón, F. (2018). Ozone therapy as adjuvant for cancer treatmen_t: is further research warranted?. Evidence-based com_pl_emen_tary and alternative medicine, 2018.

[8] Sunnen, G. V. (1988). Ozone in medicine: overview and future directions. J Adv Med, 1(3), 159-174.

[9] Menendez, S., Cepero, J., & Borrego, L. (2008). Ozone therapy in cancer treatment: State of the art. Ozone: Science and Engine_er_in_g, 30(6), 39_8-404.

[10] Tirelli, U., Cirrito, C., Pavanello, M., Del Pup, L., Lleshi, A., & Berretta, M. (2018). Oxygen-ozone therapy as support and palliative therapy in 50 cancer patients with fatigue—A sh_ort report. Eur Rev Med P_ha_rm_acol Sci, 22(22), 8030-3.

[11] Emma, B. (2012). Treatment of advanced non-small-cell lung cancer with oxygen ozone therapy and mistletoe: an integrative approach. European Journal of Integrative Medicine, (4), 130.

[12] Brinkman, R., & Lamberts, H. B. (1958). Ozone as a possible radiomimetic gas. N_at_ure, 181, 1202-1203.

[13] Sweet, F., Kao, M. S., Lee, S. C., Hagar, W. L., & Sweet, W. E. (1980). Ozone selectively inhibits growth of human cancer ce_lls. Sc_ie_nce_, 209(4459), 931-933.

[14] Zänker, K. S., & Kroczek, R. (1990). In vitro synergistic activity of 5-fluorouracil with low-dose ozone against a chemoresistant tumor cell line and fresh human tum_or cells. Ch_em_ot_herapy, 36(2), 147-154.

[15] Cannizzaro, A., Falzacappa, C. V., Martinelli, M., Misiti, S., Brunetti, E., & Bucci, B. (2007). O2/3 exposure inhibits cell progression affecting cyclin B1/cdk1 activity in SK‐N‐SH while induces apoptosis in SK‐_N‐DZ neuroblastoma cell_s. _Jo_urnal of cellular physiology, 213(1), 115-125.

[16] Simonetti, V., Quagliariello, V., Giustetto, P., Franzini, M., & Iaffaioli, R. V. (2017). Association of ozone with 5-fluorouracil and cisplatin in regulation of human colon cancer cell viability: in vitro anti-inflammatory properties of ozone in colon cancer cells exposed to lipopolysacchari_des. Evidence-Based Complementary and Alternative Med_ic_ine,_ 2017.

[17] Schulz, S., Häussler, U., Mandic, R., Heverhagen, J. T., Neubauer, A., Dünne, A. A., ... & Bette, M. (2008). Treatment with ozone/oxygen‐pneumoperitoneum results in complete remission of rabbit squa_mous cell carcinomas. Internati_on_al_ journal of cancer, 122(10), 2360-2367.

[18] Arfin, S., Jha, N. K., Jha, S. K., Kesari, K. K., Ruokolainen, J., Roychoudhury, S., ... & Kumar, D. (2021). Oxidative stress in cancer cell metabol_ism. Antioxi_da_nt_s, 10(5), 642.

[19] Viebahn-Hänsler, R., León Fernández, O. S., & Fahmy, Z. (2016). Ozone in medicine: clinical evaluation and evidence classification of the systemic ozone applications, major autohemotherapy and rectal insufflation, according to the requirements for evide_nce-based medicine. Ozone: S_ci_en_ce & Engineering, 38(5), 322-345.

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