Is ozone therapy safe? Evidence, history and what you need to know

If you're considering ozone therapy, one of the first questions you probably have is: is it safe? It's a fair question, and the answer requires looking at the history, the science, and the importance of choosing the right practitioner.

A therapy with over 200 years of history

The practice of ozone therapy dates back to the late 1700s and early 1800s, when it first showed therapeutic benefits in dentistry and medicine. Since then, it has evolved into a well-established complementary therapy used in clinics and hospitals around the world.

Today, it is estimated that there are over 30,000 professionals practicing ozone therapy worldwide, with Germany being the leader in both research and clinical application.

The scientific evidence: ISCO3

The International Scientific Committee of Ozone Therapy (ISCO3) is the body that consolidates the scientific evidence behind ozone therapy. Its library includes over 2,500 clinical studies on ozone therapy, covering everything from pain management to circulatory disorders.

ISCO3 also publishes the Madrid Declaration on Ozone Therapy, which sets the standards for safe practice — including concentrations, routes of administration and contraindications.

Safety depends on the practitioner

Ozone therapy is carried out in both clinics and hospitals, but not all clinics follow the scientific committee's protocols. This is a critical distinction:

• Safe ozone therapy is performed by a licensed physician trained in the ISCO3 protocols
• It uses medical-grade ozone at precise concentrations
• It is administered through validated routes (infiltration, insufflation, ozonized saline, etc.)
• It complements — it does not replace — conventional medicine

At Evelyn's Medical Care in Dublin, Dr. Evelyn Gaite is certified in ozone therapy and integrative medicine, and follows ISCO3 protocols. She attended the 4th ISCO3 Congress and the 4th edition of the Madrid Declaration on Ozone Therapy (2025).

What does the evidence say?

Research and clinical experience suggest ozone therapy can help with:

• Regulation of the inflammatory response — helpful for recurring respiratory or urinary infections
• Improved circulation and oxygen supply — beneficial after a heart attack or stroke caused by ischaemia
• Boosted body's recovery — especially useful after accidents, surgery, or intense sports practice
• Anti-inflammatory and pain-relieving effects — for both acute and chronic pain
• Immune system modulation — supporting the body's natural defences
• Oxidative stress modulation — helping to balance free radicals and antioxidants

The bottom line

When performed by a trained, licensed physician at appropriate doses, medical ozone therapy is safe. It is not the same as environmental ozone pollution — medical ozone is produced in a controlled clinical setting at precise concentrations.

If you're in Dublin and want to know whether ozone therapy could help you, book a consultation with Dr. Evelyn Gaite. She'll assess your medical history and determine if it's the right complementary treatment for you.