polycythemia vera

pathology

Also known as: erythremia, primary polycythemia

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Last updated

July 23, 2026

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Polycythemia vera is a condition where the body produces an excessive amount of red blood cells without a known cause. This leads to thickened blood, slowed circulation, and an increased risk of blood clots. In addition to red blood cells, white blood cells and platelets may also increase, and the spleen often enlarges.12

Individuals with polycythemia vera may experience a ruddy complexion, headaches, dizziness, and a feeling of fullness. While there's an increased risk of clotting, some individuals may also experience bleeding due to insufficient clotting factors. The disease is more common in men and often appears in middle age or later. Treatment typically involves reducing red blood cell volume through blood removal or, in some cases, medication or radiation therapy to control bone marrow activity.12

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Polycythemia vera is a condition marked by the overproduction of platelets as well as red and white blood cells; blood is drawn in such cases to prevent the formation of blood clots. Leech therapy continues to be used to reduce blood congestion in veins and prevent tissue necrosis, especially…
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Polycythemia vera is a condition marked by the overproduction of platelets as well as red and white blood cells; blood is drawn in such cases to prevent the formation of blood clots. Leech therapy continues to be used to reduce blood congestion in veins and prevent tissue necrosis, especially…
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Polycythemia differs from a disease called polycythemia vera (erythremia, or primary polycythemia), in which excess red blood cells occur without known cause. In polycythemia vera there is usually an increase in other blood elements as well; for example, the number of red cells…
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Polycythemia differs from a disease called polycythemia vera (erythremia, or primary polycythemia), in which excess red blood cells occur without known cause. In polycythemia vera there is usually an increase in other blood elements as well; for example, the number of red cells…
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