Evidence Trace, complete trial record
In plain terms
In plain terms: Ozone Therapy (Medical Ozone) shows early signals in human research but the evidence is limited -- small trials, surrogate endpoints, or not yet independently replicated. It is an emerging area, not yet a proven one.
Ozone Therapy (Medical Ozone)
C
Limited: small, mixed or unreplicated trials
The endpoint this grade is based on: self_report
The evidence as the record states it
Lopes de Jesus et al. (PLoS One, 2017; PMID 28738079): double-blind placebo-controlled trial, 98 patients with knee osteoarthritis; pain, function and quality of life improved more with injected ozone over 8 weeks. Nazarieh et al. (J Bodyw Mov Ther, 2024; PMID 38763606): double-blind placebo-controlled trial, 33 patients with knee osteoarthritis on home exercise; benefit held at 1 and 6 months. Sconza et al. (Arthroscopy, 2020; PMID 31679646): systematic review of 11 knee trials, none of good quality. Migliorini et al. (Eur J Orthop Surg Traumatol, 2024; PMID 39579218): ozone and hyaluronic acid gave similar knee pain at 4 to 6 months. Sucuoglu and Soydas (J Back Musculoskelet Rehabil, 2021; PMID 33843663): double-blind trial, 38 patients with acute lumbar disc herniation; pain and disability fell more with ozone beside the spine. Chang et al. (J Back Musculoskelet Rehabil, 2024; PMID 38905033): pooled trials; ozone into the disc did better than steroid injections at 6 months. Magalhaes et al. (Pain Physician, 2012; PMID 22430658): pooled trials of ozone for disc-related back pain, mainly against active treatments, with no placebo-controlled trial. Wainstein et al. (Diabetes Technol Ther, 2011; PMID 21751891): double-blind sham-controlled trial, 61 patients with diabetic foot ulcers; full wound closure in 41 against 33 percent, not significant. Cacciatore et al. (Med Sci (Basel), 2026; PMID 42346828): umbrella review of seven meta-analyses against inactive controls in four conditions; certainty low or very low for every outcome, and no healing benefit for diabetic foot ulcers. Filho et al. (J Wound Care, 2024; PMID 39630555): six diabetic foot ulcer trials pooled, more ulcers healed, with considerable risk of bias.
PMID 28738079 PMID 38763606 PMID 31679646 PMID 39579218 PMID 33843663 PMID 38905033 PMID 22430658 PMID 21751891 PMID 42346828 PMID 39630555
Evidence by specific use
Knee osteoarthritis pain, ozone injected into the joint
Grade C
Lopes de Jesus et al. (PLoS One, 2017; PMID 28738079): double-blind, placebo-controlled, 98 patients, 8 weeks; pain, function and quality of life scores improved more with ozone. Nazarieh et al. (J Bodyw Mov Ther, 2024; PMID 38763606): double-blind, placebo-controlled, 33 patients and 42 knees, all doing home exercise; pain and function stayed better with ozone at 1 and 6 months. Sconza et al. (Arthroscopy, 2020; PMID 31679646): of 11 randomized trials with 858 patients, none reached good quality, 2 were fair and the rest poor. Migliorini et al. (Eur J Orthop Surg Traumatol, 2024; PMID 39579218): against hyaluronic acid, pain was no different at 4 to 6 months. Two small placebo-controlled trials on a self-reported endpoint, with trial quality rated fair or poor: C. A 2026 trial of ozone mixed with dextrose and magnesium is not counted here, because it did not test ozone alone.
PMID 28738079 PMID 38763606 PMID 31679646 PMID 39579218
Low back pain from a herniated lumbar disc, ozone injected beside the spine or into the disc
Grade C
Sucuoglu and Soydas (J Back Musculoskelet Rehabil, 2021; PMID 33843663): double-blind, 38 patients, ozone beside the spine against a very low ozone dose as placebo, both on top of conservative care; pain and disability fell more with ozone, most at one month after treatment. Chang et al. (J Back Musculoskelet Rehabil, 2024; PMID 38905033): pooled trials of ozone injected into the disc; treatment success at 6 months was higher than with steroid injections and pain fell more than with medications, with results similar to microdiscectomy. Magalhaes et al. (Pain Physician, 2012; PMID 22430658): the trials pooled were mainly against active treatments and no placebo-controlled trial was found. One small placebo-controlled trial, not repeated, on a self-reported endpoint: C.
PMID 33843663 PMID 38905033 PMID 22430658
Healing of diabetic foot ulcers
Grade D
Wainstein et al. (Diabetes Technol Ther, 2011; PMID 21751891): the one double-blind, sham-controlled trial; Full wound closure did not differ by assigned group (41 against 33 percent), and only the per-protocol subset favored ozone. Cacciatore et al. (Med Sci (Basel), 2026; PMID 42346828): umbrella review of meta-analyses against inactive controls; ozone was not superior for ulcer healing (RR 1.69, 95% CI 0.90 to 3.17), low certainty. Filho et al. (J Wound Care, 2024; PMID 39630555): six trials pooled found more healed ulcers, with considerable risk of bias. The cleanest tests did not show a healing benefit: D on Route 2.
PMID 21751891 PMID 42346828 PMID 39630555
General health, aging or longevity, by blood ozonation or intravenous ozone
Grade D
Why Grade C and not Grade B
Grade C reflects early or limited human evidence -- small trials, surrogate endpoints, or preliminary findings not yet independently replicated. The evidence points in a promising direction but does not yet meet the standard for Grade B. A single well-powered, independently replicated trial with a meaningful endpoint would move this to Grade B or higher.
What this grade covers and what it does not
Grade C at the headline, from its best-supported uses, knee and back pain from injections; each use carries its own letter below. Knee osteoarthritis pain: two small placebo-controlled trials favored ozone (PMIDs 28738079, 38763606), but independent review rated the trials fair or poor (PMID 31679646): C. Back pain from a herniated disc: one small placebo-controlled trial (PMID 33843663) and pooled trials against other treatments (PMID 38905033): C. Diabetic foot ulcers: the sham-controlled trial missed its main analysis (PMID 21751891) and pooled trials against inactive controls found no healing benefit (PMID 42346828): D, tested. General health, aging or longevity: no randomized trial: D, not tested. WHY NOT B: no use has well-designed placebo-controlled trials supporting each other, and pain is a self-reported endpoint. WHAT THIS GRADE DOES NOT COVER: dental uses such as periodontitis and wisdom tooth surgery, which the 2026 umbrella review included and this record does not grade; ozonated oils on the skin; and ozone sauna cabinets.
What would move this grade
A well-powered randomized trial with an objective, clinically meaningful primary endpoint and at least one independent replication would support Grade B or higher.
How this was studied
Form: Oxygen and ozone mixture injected into a joint or beside the spine, or applied to a foot ulcer (PMIDs 28738079, 33843663, 21751891) · Dose: Ozone at 20 to 25 micrograms per milliliter for injections (PMIDs 28738079, 33843663) · Population: Adults with knee osteoarthritis, lumbar disc herniation or diabetic foot ulcers (PMIDs 28738079, 33843663, 21751891) · Duration: 8 injection sessions to 12 weeks of treatment (PMIDs 33843663, 21751891)
How to track whether this is working
Pain and function on a validated scale before and after a course, set with the treating clinician.