Bloodletting is the process of drawing blood from the body in the treatment of disease. Polycythemia is one of the few diseases in modern times that is treated by bloodletting. In this disease, the blood cells grow too rapidly. The blood becomes thick and sluggish. Bloodletting removes the excess amount of blood. It is usually done by drawing blood from a vein. In early times, barbers often performed bloodletting. Usually, it only weakened the patient. Bloodletting is also known as venesection and phlebotomy.
