Erythropoietin (EPO) is a glycoprotein hormone that plays a crucial role in the production of red blood cells in the body. It is primarily produced by the kidneys in response to low oxygen levels in the blood. EPO stimulates the bone marrow to increase the production of red blood cells, which carry oxygen to different tissues in the body. Research in the area of erythropoietin includes studying its role in various medical conditions such as anemia, chronic kidney disease, cancer-related fatigue, and neuroprotection in conditions like stroke and neurodegenerative diseases. EPO has also been used as a therapeutic agent to treat anemia in patients with chronic kidney disease and cancer, as well as to improve athletic performance in some cases. Furthermore, studies have investigated the potential of EPO as a neuroprotective agent in conditions like stroke, traumatic brain injury, and Alzheimer's disease. Research in this area continues to explore the various mechanisms by which EPO exerts its effects, as well as its potential therapeutic applications in different medical conditions.