Ozone (O₃) is an enriched oxygen molecule found naturally in the Earth's stratosphere. Its primary function is to protect the Earth from harmful ultraviolet radiation from the Sun, so that it absorbs most of that radiation. In medicine, ozone therapy is used for disinfection, treatment of certain medical conditions and damaged tissues with the help of oxygen and active stimulation of the immune system. Ozone therapy provides antibacterial, antiviral, antifungal, antioxidant and immunostimulatory effects that have been confirmed by numerous scientific studies.