Oxygen therapy is used for the follow-up treatment after stroke, heart attack or operation (e.g. ischemic heart disease, heart arrhythmia, angina pectoris episodes, arteriosclerosis, cerebrovascular diseases, forgetfulness, tinnitus, disorder of blood supply in arms and legs, some eye diseases, patients after cardiac surgeries, etc.). It is often used as a back-up during the therapy of benign tumors. Oxygen therapy can alleviate certain chronic problems related to airway diseases. It also has good effects on people with metabolic issues such as diabetes, metabolism of fats, etc.