What Does a High Red Blood Cell Count Mean?

An elevated red blood cell count is associated with dehydration, congenital heart disease, kidney tumors, bone marrow diseases and scarring of the lungs, reports MedlinePlus. Red blood cells contain hemoglobin, a protein that transports oxygen.

In men, a normal red blood cell count ranges from 4.7 to 6.1 million cells per microliter of blood, states MedlinePlus. Women have a slightly lower normal range of 4.2 to 5.4 million cells per microliter. The medications gentamicin and methyldopa are known to increase the number of RBCs in the blood. Moving to a high-altitude area can cause an increase as well. Other causes of a high RBC count include cigarette smoking, a low blood oxygen level and right-sided heart failure.