More than 2,000 years ago, the Oath of Hippocrates mandated that doctors "give no deadly medicine."
In 2002, the physicians' code of ethics that medical schools swear to is a mere shell of the original, so different than the original the father of medicine would likely not recognize it at all.
A group of doctors in the U.S. and England unveiled their new professional code of conduct last month in an effort to contemporize the oath, which Greek doctor Hippocrates was believed to have penned before his death in 377 B.C.
The new oath has its critics.
"This new document does not deserve to be called a Hippocratic Oath," said Dr. Nigel Cameron, an advisor to the Christian Doctors Association. "This new statement is the most watered-down and general of all the statements."
Most medical graduates swear to some version of the original oath. The new version, called the "Charter on Medical Professionalism," sets forth three fundamental principles and 10 professional commitments for doctors. Most address things like improving the quality of care, a commitment to honesty with patients and a call to lifelong learning.
Physicians from several international groups collaborated on the effort, including the American Board of Internal Medicine, the American College of Physicians-American Society of Internal Medicine and the European Federation of Internal Medicine.
Dr. Harry Kimball, who helped write the new oath, said it was designed to help focus doctors on what is important in an increasingly political and market-driven medical climate.
"It introduces new elements into our professional codes, which focus on the patient, and the patient's role in medical care," he said.
But in a statement, the CDA said the new oath has a number of positive elements but ignores "the value and sanctity of human life."
Hippocrates' original oath reads, in part: "I will give no deadly medicine to anyone if asked, nor suggest any such counsel; and in like manner I will not give to a woman a pessary to produce abortion."
Cameron said most medical schools ignore the oath today. "The two basic parameters were no abortion and no euthanasia," he said. "The point is, doctors just don't get into that sort of thing."
Kimball said the new charter does not get that specific. "That's a very specific issue in which people can agree or disagree. There are doctors on both sides of the issue," he said.
The oath is taken by most of the approximately 16,000 medical students who graduate from American colleges and universities each year. But only one school still recites the original oath, according to a 1993 study by doctors Robert Ro and Norman Pang.
The study found 98 percent of schools administered some form of the oath, but only eight percent of those oaths outlaw abortion and just 14 percent command against mercy killing.
The new charter also lacks an absolute ban on doctors having sexual relationships with patients, Cameron said. Under a "commitment to maintaining appropriate relations with patients," the charter reads, "physicians should never exploit patients for any sexual advantage."
"The implication is that sometimes it's [doctor-patient sexual relationships] OK, but it must not be exploitative," Cameron said. "Hippocrates' point is it's always exploitative."
Kimball agreed. "I think many would interpret it as it would be inappropriate to have sexual relations with a patient."
The new charter also calls for doctors to be more active in eliminating discrimination in health care and a "just distribution of finite resources."
"We just believe that patients have the right to be treated the same and that those resources, which are often scarce, should be distributed in a way that benefits the greatest number of the public," Kimball said. "The charter doesn't advocate for a particular system."