Clinical effectiveness of medical ozone therapy in COVID-19: the evidence and gaps map
Serra MEG, Baeza-Noci J, Abdala CVM, et al. Medical Gas Research, 2023.
- Study type
- Review
- People studied
- 271 people, across the studies it reviews
- Population
- Patients across 13 pooled clinical studies of medical ozone therapy in COVID-19
- Published
- 2023, Medical Gas Research
- Identifiers
- PMID 37077114, DOI 10.4103/2045-9912.372819
What the authors reported
An evidence-and-gaps map of 13 clinical studies (271 patients total) on medical ozone therapy for COVID-19, mostly major or minor autohemotherapy or rectal insufflation in acute, often hospitalized infection.
What limits this result
Authored by ozone-therapy society members; maps existing acute-COVID studies rather than long COVID, and includes no EBO2-specific study.
Other ozone methods, such as major autohemotherapy, that clinics cite in support of EBO2. A result for one method does not transfer automatically to another. One study rarely settles a medical question; our guides weigh each paper against the rest of the evidence.
How the study was done
- Design
- Evidence and gaps map (EGM) of clinical studies of ozone therapy in COVID-19
We aimed to build an evidence and gaps map (EGM) of OT in the COVID-19 ranking the articles found according to levels of evidence and outcomes
- Read from
- Read from the full text of the paper. Read on September 28, 2026.
Source: The paper at doi.org
What it measured
- Studies and patients included in the map
- 13 clinical studies of ozone therapy for COVID-19, involving a total of 271 patients
- Designs of the included studies (first part of the list)
- Case reports 6, randomized clinical trials 2, case and control studies 2
- Designs of the included studies (rest of the list)
- Quasi-experimental clinical study 1, observational study 1, non-randomized clinical trial 1
- Ozone therapy routes in the included studies
- Major or minor autohemotherapy, rectal insufflation and ozonized saline solution
- Ozone concentration and sessions reported for major autohemotherapy in the included studies
- Concentration ranged from 20 to 45 μg/mL, with 40 mcg/mL the most used; the number of sessions was 3-10
- Outcomes reported in the included papers (abstract list, first part)
- Improvement in clinical symptoms of COVID-19, respiratory function and oxygen saturation; reduction in hospital internment; decreases in C-reactive protein, ferritin and lactate dehydrogenase
- Absence of reported adverse events
- Listed among the reported outcomes with n = 10
- Effect sizes and risk-of-bias assessment
- The authors state they did not calculate effect sizes in a meta-analysis nor provide risk of bias assessments
Source: The paper at doi.org
Safety as reported
Authors report very few adverse events: mild meteorism (sensation of gas) and epistaxis that was associated with the use of heparin
Source: The paper at doi.org
Funding and conflicts
The authors declare that they have no conflicts of interest
Source: The paper at doi.org
Where we cite this study
Does EBO2 (EBOO) Work? The Evidence, Study by Study
Every study in our EBO2 (EBOO) library in one place: design, size, what was measured and found, its limits, and a check for any study a clinic cites.
EBO2 (EBOO) for Long COVID: What Clinics Claim and What Has Been Studied
What clinics claim about EBO2 (EBOO) for long COVID, the post-COVID ozone studies and their limits, what the FTC and FDA said, and what CDC calls care.
EBO2 (EBOO), Blood Thinners, and Other Medicines: What the Sources Say and What to Ask
How EBOO circuits are kept from clotting, what heparin's FDA label warns, what clinics say about blood thinners, and what no source has studied.