Ozone-induced encephalopathy: A novel iatrogenic entity
Haggiag S, Prosperini L, Stasolla A, Gerace C, et al. European Journal of Neurology, 2021.
- Study type
- Case series
- People studied
- 3 people
- Population
- Three patients (men aged 59 and 27, a woman aged 56) with neurological symptoms immediately or 5 minutes after cervical or lumbar ozone therapy
- Published
- 2021, European Journal of Neurology
- Identifiers
- PMID 33657263, DOI 10.1111/ene.14793
What the authors reported
Three patients had neurological symptoms immediately or 5 minutes after cervical or lumbar ozone therapy, among them loss of consciousness, cortical blindness, visual impairment, and vertigo. Brain MRI was normal except a subtle cerebellar change on one follow-up scan; two had a patent foramen ovale. All recovered fully within 48 hours. The authors found eight more cases in the literature.
What limits this result
Three cases, read from the abstract only. The authors describe the findings as suggestive of ozone-induced encephalopathy, a term they introduce, and state that it likely has a complex pathogenesis; the abstract gives no ozone doses or volumes and no follow-up beyond recovery within 48 hours.
Harms reported after ozone therapy, and studies of how ozone exposure affects health. One study rarely settles a medical question; our guides weigh each paper against the rest of the evidence.
How the study was done
- Design
- Three case reports with a review of the literature
Three cases with findings suggestive of OIE are presented, and the literature is reviewed.
- Setting
- Neurology Department, San Camillo Forlanini Hospital, Rome, Italy (author affiliation)
- Read from
- Read from the abstract only; where this page says nothing about an item, the abstract does not report it. Read on October 2, 2026.
Source: Abstract on PubMed
Study arms
| Group | Participants | What they received |
|---|---|---|
| Case 1: healthy 59-year-old man | Not reported | Cervical ozone-therapy session for chronic neck pain; symptoms immediately after |
| Case 2: 56-year-old woman | Not reported | Lumbar ozone therapy; all her symptoms began immediately after |
| Case 3: healthy 27-year-old man | Not reported | Cervical ozone injection; vertigo and mild blurred vision 5 min later |
Source: Abstract on PubMed
What it measured
- Case 1 symptoms
- Loss of consciousness, cortical blindness, restlessness, and anterograde amnesia immediately after the session
Case 1 is a healthy 59-year-old man presenting with loss of consciousness, cortical blindness, restlessness, and anterograde amnesia immediately following a cervical ozone-therapy (OT) session for chronic neck pain.
- Case 1 brain MRI on admission
- Normal
- Case 1 follow-up scan and echocardiography
- Subtle increased T2 fluid-attenuated inversion recovery signal within the left cerebellum; patent foramen ovale
- Case 2 history and symptoms
- History of migraine, PFO, and lumbar pain; headache, bilateral visual impairment, motor dysphasia, and agitation
- Case 2 brain MRI
- Negative
- Case 3 neurological examination and brain MRI
- Normal
- Recovery
- All three patients had full recovery within 48 h
- Literature review
- Eight additional cases of ozone-induced encephalopathy found
Source: Abstract on PubMed
Safety as reported
Central nervous system toxicity after ozone-based treatments, which the authors term ozone-induced encephalopathy (OIE)
Source: Abstract on PubMed
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.
Ozone Therapy Adverse Events by Route: What Case Reports Show, and Where EBO2 (EBOO) Fits
Every ozone therapy adverse event we could read in case reports and series, grouped by route, plus how to search FDA's MAUDE data and report to MedWatch.