The Potential Toxicity of Ozone: Side Effects and Contraindications of Ozonetherapy

Ozone in the adjunct medical treatment. The round personality of a molecule with hormetic properties

Ozone, an allotrope of oxygen, is enjoying an increasing interest in the setting and management of the medical adjunct treatment, which is called, maybe too simplistically, "ozone therapy". Ozone is not a medicine, so the word therapy does not properly fit this gaseous molecule. Like many natural compounds, for example plant flavonoids, even ozone interacts with aryl hydrocarbon receptors (AhRs) and, at low doses, it works according to the paradoxical mechanism of hormesis, involving mitochondria (mitohormesis). Ozone, in the hormetic range, exerts cell protective functions via the Nrf2-mediated activation of the anti-oxidant system, then leading to anti-inflammatory effects, also via the triggering of low doses of 4-HNE. Moreover, its interaction with plasma and lipids forms reactive oxygen species (ROS) and lipoperoxides (LPOs), generally called ozonides, which are enabled to rule the major molecular actions of ozone in the cell. Ozone behaves as a bioregulator, by activating a wide population of reactive intermediates, which usually target mitochondria and their turnover/biogenesis, often leading to a pleiotropic spectrum of actions and behaving as a tuner of the fundamental mechanisms of survival in the cell. In this sense, ozone can be considered a novelty in the medical sciences and in the clinical approach to pharmacology and medical therapy, due to its ability to target complex regulatory systems and not simple receptors.

The role of ozone therapy in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (COVID-19): a review

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has rapidly swept across the world. As new knowledge regarding treatment options for COVID-19 has emerged, the use of ozone therapy in the context of SARS-CoV-2 infection as an integrative therapeutic option supplementary to standard treatment regimen has been assessed in the present literature. We reviewed, critically analyzed, and summarized all present published literature on ozone therapy in association with COVID-19 via the PubMed database. Various reports and studies on the use of ozone (major autohemotherapy, rectal ozone insufflation, ozone inhalation) in patients affected by COVID-19 indicate that ozone therapy may reduce morbidity and accelerate recovery, while exhibiting a high safety profile with no relevant adverse effects. Current literature suggests that integrating ozone therapy into the existing standard of care and best available therapy for the treatment of COVID-19 patients offers major advantages in terms of superior clinical outcome parameters and amelioration of laboratory results. Further prospective studies are warranted to guide the next steps in the clinical application of ozone therapy and examine its impact on the course of COVID-19.

Ozone as an adjuvant therapy for COVID-19: A systematic review and meta-analysis

OBJECTIVE

Ozone adjuvant in COVID-19 management showed conflicting results in prior studies. Here, we aimed to comprehensively evaluate benefits and side effects of ozone as adjuvant therapy in COVID-19 patients.

METHODS

Systematic searches were conducted in MEDLINE, ScienceDirect, Cochrane Library, Springer, medRxiv, and ProQuest for articles investigating ozone as adjuvant therapy in COVID-19. Clinical and laboratory outcomes, mortality, length of hospital stay, intensive care unit (ICU) admission, and adverse events were assessed.

RESULTS

Thirteen studies were included in this review. Case-control studies, but not randomized controlled trials (RCTs), showed a decrease in mortality following ozone therapy (OR = 0.24 (95% CI [0.07-0.76]), p = 0.02, I² = 0%, fixed-effect). However, ozone therapy did not improve the length of hospital stay (SMD = -0.99 (95 %CI -2.44 to 0.45), p = 0.18, I² = 84%, random-effects) and ICU admission (RR = 0.57 (95 %CI [0.05-6.71]), I² = 73%, p = 0.65, random-effects). Consecutive case control studies suggested that ozone therapy significantly improved levels of D-dimer (p = 0.0060), lactate dehydrogenase (LDH; p = 0.0209), C-reactive protein (CRP; p = 0.0040) and interleukin (IL)-6 (p = 0.0048) as compared to standard therapy alone.

CONCLUSIONS

The beneficial effect of ozone in COVID-19 management seems to be limited to the improvements of laboratory parameters among severe patients, including the reduction of IL-6, LDH, CRP, and D-dimer levels. Meanwhile, other study endpoints, such as mortality, length of stay and ICU admission, were not improved following ozone therapy, although it may partly be due to a shorter duration of viral clearance. Furthermore, no serious adverse event was reported following ozone therapy, suggesting its high safety profile. (PROSPERO ID: CRD42021278018).

Local Ozone Therapy in Complex Treatment of Venous Leg Ulcers: Ozone therapy for venous leg ulcers

A significant health problem in many countries of the world is the occurrence of hard to heal leg ulcers. In recent years modern methods of physical medicine in comprehensive treatment have been used often including ozone therapy. The study included 54 patients, 25 male and 29 female in age between 39 and 87 years (mean age: 66.7 ± 11.9 years) with venous leg ulcers who underwent a cycle of local ozone therapy. The progress in wound healing was evaluated by computerized planimetry and pain intensity was assessed with use a visual analog scale (VAS) . As a result of the applied local ozone therapy a statistically significant reduction of the ulcer area was achieved from median 7.1 (5.6-9.4) cm2 to 4.4 (3-7) cm2 (P = .000001), which was on median 38.74 (27.27-51.42)% compared to the baseline values ​​before the start of the therapy. In 2 patients (3.7%) the ulcers were completely healed. 18 patients (33.3%) achieved a reduction in ulcer area of ​​more than 50% of the baseline value and the remaining 34 patients (63%) also achieved a reduction in ulcer area. A statistically significant in the percentage of surface area was observed in the group of 19 patients suffering from > 5 years of age compared to the group of 35 patients suffering from ≤5 years (median 50 (32.03-67.16)% versus 33.96 (23.71-45); P = .033178), while percentage changes in ulcer surface area did not differ significantly between all other subgroups of patients. There was also a statistically significant reduction in the intensity of pain in VAS scale in all patients, median 6 (5-7) points before treatment versus 4.4 (3-7) points after treatment, P = .000001). Local ozone therapy of venous leg ulcers accelerate the healing process of ulcers in objective planimetric assessment and reduce the intensity of pain ailments.

Complementary and Alternative Therapies in Oncology

Cancer is the second leading cause of death worldwide, after cardiovascular diseases. Increasing patients’ awareness and providing easier access to public information result in greater interest in alternative anticancer or unproven supportive therapies. Fear of cancer and limited trust in the treating physician are also important reasons leading patients to seek these methods. Trust and good communication are essential to achieving truthful collaboration between physicians and patients. Given the popularity of CAM, better knowledge about these alternative practices may help oncologists discuss this issue with their patients. This article objectively reviews the most common unconventional therapies used by cancer patients.