Erythropoietin is a hormone that your kidneys naturally make to stimulate the production of red blood cells. High or low levels of erythropoietin can cause health problems. A healthcare provider can measure your erythropoietin levels with a blood test.
Erythropoietin (ih-rith-roh-POY-uh-tin) is a hormone that your kidneys primarily produce. Erythropoietin (EPO) helps your body maintain a healthy amount of red blood cells (erythrocytes).
There’s also a synthetic (man-made) form of erythropoietin that healthcare providers use to treat anemia that results from chronic kidney disease. Some athletes improperly use this drug to boost their performance because EPO increases the availability of oxygen to their muscles.
Other names for erythropoietin include erythropoetin, hematopoietin and hemopoietin.
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EPO helps make red blood cells. Red blood cells deliver oxygen to the tissues in your body. Oxygen turns into energy, and your tissues release carbon dioxide. Your red blood cells also transport carbon dioxide to your lungs for you to exhale.
Normally, when specialized cells in your kidneys detect low blood oxygen levels, they increase the production of EPO. EPO then tells the spongy tissue inside your bones (bone marrow) to make more red blood cells.
When cells in your kidneys sense that there’s sufficient oxygen in your blood, they reduce the production of erythropoietin.
Certain conditions can affect how much EPO your kidneys make. They may make too much or not enough. This results in low levels of red blood cells or high levels of red blood cells.
Inappropriately high levels of erythropoietin can cause high levels of red blood cells. Another name for high levels of red blood cells is polycythemia.
Long-term (chronic) exposure to low levels of oxygen can increase your EPO levels. This may be due to chronic smoking or living in a high-altitude environment where air oxygen levels are lower. Elevated EPO from a high-altitude environment is normal and appropriately high.
Anemia may not result from kidney disease and still cause high EPO levels. Anemia happens when you don’t have enough red blood cells or your red blood cells don’t work as they should. It can cause high levels of EPO because your kidneys sense that you don’t have enough red blood cells so they release extra EPO. This is a normal and appropriately high level of EPO.
In rare cases, certain tumors can also cause your kidneys to release inappropriately excessive EPO.
Chronic kidney disease (CKD) is the most common cause of low EPO levels. Damaged kidneys can’t produce as much EPO, leading to low levels. CKD and low EPO levels can lead to anemia.
Polycythemia vera can also lead to low levels of EPO. Polycythemia vera is a type of blood cancer that causes your bone marrow to make too many red blood cells due to a genetic mutation. It causes low EPO levels because your kidneys sense that you have enough red blood cells, so they don’t produce as much EPO.
Treating low levels of EPO requires treating the underlying cause.
The most common treatment to directly correct anemia due to low EPO levels is recombinant erythropoietin (erythropoietin-stimulating agents or ESAs). This is an artificial (synthetic) version of natural EPO. Healthcare providers clone the gene for EPO and give them to you by injection (shot) to stimulate the production of more red blood cells.
Providers use it to treat anemia that results from chronic kidney failure. They also give it to some people with rare types of cancer.
ESAs may cause:
A healthcare provider can measure your EPO through a blood test. A blood test helps determine what may cause a change in your blood cells that affects the release of EPO, including polycythemia, anemia or other bone marrow conditions.
They’ll disinfect the skin around a vein in your arm with iodine, isopropyl alcohol or another skin cleaner. They’ll then use a thin needle (21 gauge, slightly smaller than the size of a standard earring) to withdraw a small amount of blood from a vein in your arm. They’ll send your blood sample to a lab for analysis.
Once the lab finishes testing your blood sample, a healthcare provider will contact you to discuss your test results and answer any questions.
Even if your EPO levels are within a normal range, you may still require treatment.
Healthcare providers measure EPO in your blood in milliunits per milliliter (mU/mL). A normal range for your EPO levels may be between 4 and 26 mU/mL.
Your EPO test results may vary according to several factors, including your:
Your healthcare provider will carefully interpret your results and let you know if your levels are healthy or out of range.
If you have CKD or any anemia with low EPO, the following diet and lifestyle changes can help boost EPO levels:
A note from Cleveland Clinic
Erythropoietin is an important and essential hormone that tells your bone marrow when to make more red blood cells. However, sometimes your body inappropriately produces too many or too few red blood cells, which can cause health problems. A healthcare provider can order a blood test to see how much EPO you have in your blood and recommend the proper treatment.
Last reviewed by a Cleveland Clinic medical professional on 11/10/2022.
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