Polycythemia is a condition that occurs when the bone marrow produces an abnormal and excessive amount of red blood cells and platelets in the blood. The abnormal increase of red blood cells in the blood can cause the blood to thicken and clot.

There are several forms of polycythemia—primary polycythemia, secondary polycythemia, and stress polycythemia. Each form has its own set of causes and risk factors.

Location of Active Bone Marrow in an Adult

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Nearly all cases of primary polycythemia are believed to be caused by a mutation in the janus kinase 2 gene (JAK2).

Risk Factors

Primary polycythemia is more common in men and people over the age of 40 years of age. It is also more common in people who are Caucasian or those of Ashkenazi Jewish descent.


The symptoms of primary polycythemia occur gradually and vary from person to person. Some people show no signs of the condition. Symptoms may include:

  • Abnormal and heavy bleeding due to a cut or a nosebleed
  • Intense and frequent bone pain and/or muscle pain
  • Headaches, lightheadedness, or gastrointestinal symptoms
  • Vision problems
  • Ringing in the ears
  • Difficulty or labored breathing
  • The color of the skin appears reddish
  • Fatigue
  • Inability to concentrate
  • Intense itching after a warm or hot bath, shower, or any activity that requires soaking your skin in warm or hot water


You will be asked about your symptoms and medical history. A physical exam will be done. You may be referred to a doctor called a hematologist who specializes in blood diseases and disorders. The hematologist will perform a tests.

Your bodily fluids may be tested. This can be done with:


Talk with your doctor about the best treatment plan for you. Treatment options include the following:


Phlebotomy is a technique that requires a person to periodically have blood removed from a vein to decrease the overall total proportion of red blood cells in the body. The frequency of the treatment is based on how quickly a person’s bone marrow produces an excessive amount of red blood cells.


Chemotherapy is a group of drugs that can be given by mouth, by injection, or through a tube that is inserted into a duct or blood vessel to slow the rapid development of red blood cells in the bone marrow.


You may be given aspirin to reduce your risk of blood clots and spleen removal.


There are no known preventative measures that will reduce your chances of getting primary polycythemia.

There is no cure, but recent research suggests that individuals who have primary polycythemia may significantly increase their overall life expectancy by seeking treatment right away.