What do excessive erythrocytes result in?

Excessive erythrocytes, a condition known as erythrocytosis, can lead to increased blood viscosity, which may impair blood flow and elevate the risk of thrombotic events such as strokes or heart attacks. This thickened blood can strain the cardiovascular system, potentially resulting in hypertension and other complications. Additionally, the increased red blood cell mass can cause symptoms like headache, dizziness, and fatigue.