Medical ozone used in medicine is derived by conversion of oxygen (O2) to O3. Ozone is an antioxidant and activates immune system. The aim of applications of medical ozone is activating the circulation and besides regenerating the altered organic functions during many illnesses. Medical ozone is shown to be effective for acute and chronic painful intraarticular injections, acute and chronic joint illnessess including knee and shoulder disorders and for antiaging purposes. These effects are thought to be mediated by induction of IFN-beta, activation of superoxide dismutase and induction of TGF-beta. The success rate for medical ozone in pain therapy is 50-60%. In our clinical practice, medical ozone is used in intraarticular injections (knee and shoulder), transforaminal anterior epidural, intradiscal injections.