High red blood cell count

Mayo Clinic Health Manager

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High red blood cell count may occur because:

Red blood cell production increases to compensate for low oxygen levels due to poor heart or lung function
Your kidneys release too much of a protein (erythropoietin, or EPO) that enhances red blood cell production
Your bone marrow is producing too many red blood cells
The oxygen-carrying capacity of red blood cells is impaired
Red blood cells are compensating for a limited oxygen supply in higher altitudes
The loss of blood plasma, the liquid component of blood, creates relatively high levels of red blood cells

Specific causes of high red blood cell count may include:

Anabolic steroids, which stimulate red blood cell production
Congenital heart disease
COPD
Dehydration
EPO doping — injections of erythropoietin (EPO) to enhance athletic performance
Heart failure
Hemoglobinopathies — conditions present at birth that impair the oxygen-carrying capacity of your red blood cells
Kidney cancer
Living at a high altitude, where there's less oxygen in the air
Other types of heart disease
Other types of lung disease
Polycythemia vera
Pulmonary fibrosis
Smoking, which may result in low blood oxygen levels

Causes shown here are commonly associated with this symptom. Work with your doctor or other health care professional for an accurate diagnosis.

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