This is a concern for men who take testosterone, because the addition of testosterone can increase the red blood count in anyone. If there is an underlying condition that also elevates the red blood count, it is important to diagnose and treat that condition early while being treated with testosterone. The reason it is important is that increased concentrations of red blood cells can lead to sludging of the blood and could cause blood clots (an embolism) to form.

It is important that this condition (called polycythemia) is diagnosed and treated prior to, or early during a course of testosterone replacement. Evaluation of elevated hematocrit determines whether you have Hemochromatosis, a benign elevation of red blood cells, or a Jak 2 genetic defect which has other far-reaching consequences with or without testosterone replacement. We can also determine whether your situation requires a specialist such as a hematologist/oncologist.