Whose oath do doctors take?

Hippocrates of Kos, who lived from about 460 to 370 BC, is often called the father of medicine because he argued that diseases have natural causes rather than being punishments from the gods. The Hippocratic Oath, written in his era and possibly by his followers, commits physicians to help the sick, keep patient confidences and avoid causing harm. The original version begins by swearing by Apollo and other Greek gods. The famous phrase first, do no harm does not actually appear in the oath; a similar idea appears in another Hippocratic work, Epidemics. Many medical schools now use modern versions, such as the Declaration of Geneva adopted by the World Medical Association in 1948.