To browse other articles on a range of HSL topics, see the A-Z index.
Bloodletting is the ancient practice of opening a vein to release some blood since its "excess" was thought to be the cause of illness and disease. It is important to understand why bloodletting was a popular form of treatment from Hippocrates through Galen and consistently over the next 1700 years to the 19th century. Back to Hippocrates' time, human health was said to be based on a balance of the four humors: blood, phlegm, black bile and yellow bile. Each was linked to a specific organ — brain, lung, spleen and gall bladder — and to personality types such as sanguine, phlegmatic, melancholic and choleric. Therefore, being ill meant that the four humors were out of balance; removing an excess was therefore indicated. Accordingly, health practitioners used one of the following to restore health: bloodletting, purging, catharsis, diuresis and so on.
By the 1st century, bloodletting was widely-used and, later, once Galen had declared blood to be the most dominant humor, venesection became popular. Throughout human history, bloodletting has been practiced by various groups such as the Mesopotamians, Egyptians, Greeks, Mayans and Aztecs. In fact, bloodletting was practiced throughout Europe and the Americas well into the 19th century. In 1799, George Washington fell ill with an infection, and subsequently was bled by an employee and later by three doctors. He died later that day, and bloodletting likely hastened his death. Today, most people know bloodletting is ineffective in treating diseases. The irony is that its practitioners believed in bloodletting even though it signicantly weakened patients.
Bloodletting (or phlebotomy) is used in 21st century medicine for the treatment of hemochromatosis, polycythemia vera and porphyria cutanea tarda. The use of leeches in medicine is a form of bloodletting.