A high hemoglobin count occurs most commonly when your body requires an increased oxygen-carrying capacity, usually because:

  1. You smoke
  2. You live at a high altitude and your red blood cell production naturally increases to compensate for the lower oxygen supply there

High hemoglobin count occurs less commonly because:

  1. Your red blood cell production increases to make up for chronically low blood oxygen levels due to poor heart or lung function.
  2. Your bone marrow produces too many red blood cells.
  3. You've taken drugs or hormones, most commonly erythropoietin (EPO), that stimulate red blood cell production. You're not likely to get a high hemoglobin count from EPO given to you for chronic kidney disease. But EPO doping — getting injections to enhance athletic performance — can cause a high hemoglobin count.

If you have a high hemoglobin count without other abnormalities, it's unlikely to indicate a related serious condition. Conditions that can cause a high hemoglobin count include:

  1. Congenital heart disease in adults
  2. COPD (chronic obstructive pulmonary disease) exacerbation — worsening of symptoms
  3. Dehydration
  4. Emphysema
  5. Heart failure
  6. Kidney cancer
  7. Liver cancer
  8. Polycythemia vera

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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Dec. 02, 2020