What is it?

Polycythemia is an increased amount of red blood cells in the blood stream. This causes our blood to thicken or bocome more viscose, which may cause variouse symptoms and complications. Red blood cells are responsible for carrying oxygen to the cells in our body. Thickened blood flows more slowly, thus the amount of oxygen reaching the tissues is reduced. In addition, thickened blood is more prone to blood clot formation. These clots can block blood flow to the brain or other organs, causing a stroke or even death. Risk factors include obesity, exessive alcohol use, hypertension and smoking.

The causes are commonly divided into primary and secondary. Primary polycythemia is caused due to a problem in the red blood cell producing cells in the bone marrow whereas secondary polycythemia is caused by another underlying condition. It is important to know that volume depletion may also cause polycythemia. This polycythemia can be reversed by giving fluids.

1. Primary polycythemia- The most common cause for primary polycythemia is a condition called polycythemia vera. This is a type of blood cancer that causes over production of red blood cells.
2. Secondary polycythemia- Common causes for secondary polycythemia include sleep apnea, obesity, smoking, hypoventilation and chronic obstructive pulmonary disease. High altitude may also cause secondary polycythemia. Since our red blood cells are responsible for carrying oxygen to the cells in our body, and oxygen levels are lower in high altitude, our body compensates by over-production of red blood cells. Some cancers may also cause polycythemia.

68 Alikes with Polycythemia

Learn from others
who are experiencing

Additional names

This group contains additional names:
- Polycythemia Vera

Signs & symptoms

Polycythemia is often asymptomatic and is incidentally diagnosed.
Symptoms may include fatigue, breathing difficulties, chest pain, weakness, headaches, concentration problems, tinnitus (the perception of noise or ringing in the ears), blurred vision and more. Clot formation due to the viscose blood may cause stroke, myocardial infarction, deep vein thrombosis and more.
Symptoms that are associated with polycythemia vera include erythromelalgia (a burning pain in the feet or hands accompanied by redness and pallor), itchiness (especially after a warm shower), unexplained weight loss and fever.


It is important to determine the cause in order to treat properly.
CBC (complete blood count)- This is a common blood test that gives information about the different cells that circulate in your blood. It includes information about white blood cells, red blood cells, and platelets. In polycythemia, there will be abnormally high levels of hemoglobin and/ or hematocrit (the concentration of red blood cells in your blood stream). There may also be abnormally high levels of white blood cells or platelets.
After diagnosis, the doctor will take a medical history in order to determine the cause and uncover complications of the polycythemia. The doctor will then ask for more tests in accrdance with the suspected cause.These tests may include:
Pulse oxymetry
EPO levels
JAK 2 genetic testing
Serum chemistries
Bone marrow examination


The two main treatments for polycythemia are low dose aspirin and phlebotomy. Low-dose aspirin is given in order to thin your blood and reduce your risk of stroke (thrombosis). Phlebotomy or bloodletting, the removal of a small amount of blood from one of your veins, is done in order to reduce your red blood cell count. In the beggining, the treatments are usually done on a weekly basis but are later less frequent. Other treatments may be given to high risk patients like older patients or those with a history of thrombosis. These medications include hydroxyurea, interferon alpha, Ruxolitinib and more. Other treatments may be needed according to the cause.

☝️ This is not a substitute for professional medical advice. Please consult with your physician before making any medical decision.

Learn more about our editorial process for content accuracy.

Latest discussions

More from the Diabetes Type 2 (T2D) community

Alike Wisdom

Instantly get answers to medical questions with our AI, built from the collective wisdom of our community facing similar experiences

Thank you! Your submission has been received!

Find people who are
experiencing a similar
medical reality

100% Free