Ozone therapy has been attracting growing interest in recent years, both in medical circles and among the general public. But this interest also brings with it some misplaced expectations.

In this post, I want to explain what medical ozone is, how it acts in the body, in which contexts it can be considered as a supportive complementary approach, and for whom it is not appropriate.

Table of Contents

What Is Medical Ozone? How It Differs from Atmospheric Ozone

Ozone (O₃) is a reactive molecule consisting of three, not two, oxygen atoms. Stratospheric ozone found naturally in the upper atmosphere and medical ozone are different things; they should not be confused with one another.

Medical ozone is produced from pure oxygen using devices certified specifically for medical use. It undergoes a controlled production process with defined standards for concentration and purity. It has no connection whatsoever to atmospheric pollution, vehicle exhaust, or industrial emissions.¹

The gas used in medical ozone applications consists of a mixture of 95-99% oxygen and 1-5% ozone. This ratio and purity enables therapeutic effect while also defining the safety threshold. It is not applied directly to the respiratory tract; at high concentrations it can irritate the airways, and for this reason it is not administered by inhalation.

How Does It Act in the Body?

The effects of ozone in the body are explained by the temporary and controlled formation of reactive oxygen species (ROS). These reactive molecules exert their effects indirectly by stimulating antioxidant defence systems.²

The main mechanisms of action can be summarised as follows:

Supporting antioxidant systems: Ozone exposure may temporarily increase the activity of enzymes such as glutathione peroxidase, catalase, and superoxide dismutase. These enzymes play a role in reducing cellular oxidative stress.³
Positive effects on microcirculation: Studies suggest it may increase the deformability of red blood cells; this could positively influence blood flow at the tissue level.
Antimicrobial properties: Ozone demonstrates inactivating effects against pathogens such as bacteria, viruses, and fungi under in vitro conditions; this property is being investigated particularly in local applications.
Immunomodulatory effect: Some research suggests that ozone may temporarily regulate the response profile of immune cells. This effect varies according to specific cell types and the method of application.

All of these mechanisms are observed within specific concentration ranges and under controlled application conditions. At very low concentrations the effect may be insufficient; at very high concentrations the risk of unwanted oxidative damage increases. This balance explains why standard devices and protocols are mandatory in medical ozone applications.²

Important note: These mechanisms should be understood within a supportive framework. It must be emphasised that claims such as “it cures disease” or “it prevents cancer” have not been scientifically proven. Ozone therapy is not a standalone treatment for any disease; it is considered as a supportive approach, in addition to standard medical treatment. Should be discussed with your physician before use.

For What Purposes Is It Considered Supportive?

Clinical research has examined the possibility that ozone therapy may have a supportive role in various areas. Studies in the literature exist on the following topics:⁴

Chronic wound support: Research into whether local ozone applications may positively influence the wound healing process, particularly in diabetic foot wounds and wounds that are slow to heal, has yielded promising findings.
Circulatory support: It is being investigated for the purpose of supporting microcirculation in peripheral circulatory problems.
General support: It is applied in situations of heightened oxidative stress for the purpose of supporting antioxidant systems.

In these applications, ozone is positioned not as a curative agent in itself, but as a tool that supports an existing treatment process. Ozone therapy is a supportive, complementary approach, not a replacement for any primary treatment.

Another important point: for ozone therapy to have an observable contribution in cases where it has a supportive role, the standard treatment for the underlying disease must be ongoing. For example, in a patient with a diabetic foot wound, ozone application cannot substitute for blood sugar regulation and appropriate antibiotic therapy; it is considered in addition to these treatments. In a patient with immune problems, ozone support cannot replace the necessary medical follow-up and, where required, medical treatment.

Methods of Application

Medical ozone has more than one method of application; each has a different target area and intended use.

Major Autohemotherapy

Blood taken from the patient is enriched with ozone and returned to the patient. This is a systemic application and is among the most commonly used methods. Blood is drawn and returned via the vascular route; by means of the oxygen-ozone mixture it contains, it aims to influence blood cells and provide systemic-level support.

Major autohemotherapy is generally performed within a sterile, closed system. The process is planned according to the patient’s general state of health, tolerance, and intended support objective. Patients generally tolerate the application well; adherence to environmental conditions and sterility standards is the primary safety requirement.

Local Application Methods

Local methods such as the application of ozonated water to the wound area, the use of ozonated oil, and rectal insufflation are also available. These methods are used in specific clinical situations with specific objectives. Which method is appropriate is determined entirely by clinical assessment; not every method is suitable for every patient.

Local applications are more frequently preferred, particularly in chronic wound care. Applying ozone gas or ozonated liquid to the wound surface may make a positive contribution to wound cleaning and the healing process. The most important factors determining the effectiveness of these methods are: duration of application, wound type, and control of the underlying disease.

Dose and session number in these applications are determined not according to a standard protocol, but individually according to each patient’s condition, tolerance, and intended objective.

An Important Frame: Ozone Therapy Is Not a Standalone Treatment

I discuss this point separately with every patient. Ozone therapy does not replace standard medical treatment in diabetic foot wounds, venous insufficiency, pain management, or immune support. These patients must continue using necessary medications and treating their diabetes or varicose vein problem at the same time; ozone should only be considered as an addition to this treatment.⁵

Presenting any agent as “it treats everything” is neither scientifically valid nor beneficial to the patient. In ozone therapy, realistic expectations, appropriate patient selection, and integration with standard treatment are the fundamental conditions for a good outcome.

Medical Ozone versus Atmospheric Ozone: Why This Distinction Matters

I want to emphasise this distinction because a significant proportion of patients ask: “Isn’t ozone harmful? They talk about ozone in air pollution.” The substance referred to as “bad ozone” in atmospheric pollution measurements is a dirty mixture formed from the reaction of nitrogen oxides with sunlight at ground level. It irritates the respiratory tract and worsens asthma.

Medical ozone, on the other hand, is obtained by the controlled electrical discharge conversion of pure oxygen. It is a sterile gas mixture, free of pollutants, with a defined concentration. It is not administered to the respiratory tract; in systemic applications it is administered via the blood, and in local applications directly to the target area. Its use in medicine has a long history dating back to the beginning of the 20th century.¹

For Whom Is It Not Appropriate?

Ozone applications are not safe for every patient. Contraindications that I must assess before carrying out an application include:

G6PD enzyme deficiency (Favism): In this genetic condition, ozone exposure may lead to the risk of serious haemolytic anaemia; it is an absolute contraindication.³
Active bleeding or severe coagulation disorder: Because blood is drawn and returned in major autohemotherapy, coagulation problems may increase risk.
Pregnancy: Elective supportive applications are generally deferred during pregnancy.
Hyperthyroidism and thyrotoxicosis: Controlled study data is insufficient; careful assessment is required.
Active heart failure: A risk-benefit assessment must be made due to systemic effects.

This list is not exhaustive. Individual assessment must always be carried out with a physician.

Frequently Asked Questions

Does ozone therapy treat a disease?

No. The available scientific evidence indicates that ozone therapy is a supportive approach. It may support the body’s own systems through specific mechanisms; however, it cannot be used as a standalone treatment for any disease and is not described as such.

Is ozone therapy safe?

When properly monitored, with correct patient selection and with contraindications such as G6PD excluded, the general safety profile is at an acceptable level. However, direct administration to the respiratory tract or application in non-isolated environments increases risk. It must always be performed under medical supervision.

How many sessions are administered?

The number of sessions is not a standard protocol. It is determined by the intended objective, the patient’s condition, and their response. Stating a definite number from the outset is not the correct approach; the plan is updated following initial assessment and initial applications.

Is ozone therapy suitable for diabetic wounds?

Research into the potentially supportive role of local ozone applications in diabetic wound care presents encouraging findings. However, these applications must always be carried out together with diabetes management, wound care protocols, and surgery where necessary; ozone should not be thought of as sufficient on its own.

Can “cancer treatment” be performed with ozone?

No. This claim lacks a scientific basis and is misleading. Oncology treatments are conducted according to evidence-based protocols. There is no sufficient and reliable clinical evidence demonstrating the efficacy of ozone therapy in cancer treatment. Telling a cancer patient that ozone is “curative” is both unethical and may divert them from evidence-based treatment.

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References

Elvis AM, Ekta JS. Ozone therapy: A clinical review. J Nat Sci Biol Med. 2011;2(1):66-70. PubMed PMID: 22470237. https://pubmed.ncbi.nlm.nih.gov/22470237/
Sagai M, Bocci V. Mechanisms of Action Involved in Ozone Therapy. Med Gas Res. 2011. PubMed PMID: 22470237. https://pmc.ncbi.nlm.nih.gov/articles/PMC3312702/
Izadi M, et al. Ozone therapy for skin diseases: Cellular and molecular mechanisms. Int Wound J. 2023. PubMed PMID: 36527235. https://pubmed.ncbi.nlm.nih.gov/36527235/
Clavo B, et al. Ozone therapy: Mechanisms and clinical applications – A review. Bioinformation. 2025. PubMed PMID: 41466669. https://pubmed.ncbi.nlm.nih.gov/41466669/
NHS. Vitamins and minerals: Overview. https://www.nhs.uk/conditions/vitamins-and-minerals/

Op. Dr. Onur Üstünel
Cardiovascular Surgery Specialist