Why is the medical symbol a snake on a stick?

The image of snakes wrapped around a stick is familiar in the medical field, decorating pharmaceutical packaging as well as hospitals. Snakebites are usually bad news, and so the animal may seem ill-suited as a symbol of the medical profession, but the ancient emblem actually has quite a history behind it.

There are actually two versions of the symbol. The winged version is known as the caduceus, and the staff is actually a staff carried by the Olympian god Hermes. In Greek mythology, Hermes was a messenger between gods and humans (which explains the wings) and a guide to the underworld (which explains the staff). Hermes was also the patron saint of travellers, which makes his connection to medicine fitting as, in ancient times, physicians had to walk great distances to visit their patients.

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In one version of the myth of Hermes, he receives the staff from Apollo, the god of healing. In another version, he receives the staff of Zeus, the king of the gods, and he is entwined with two white ribbons. The ribbons were later replaced by serpents, as a story goes that Hermes used the staff to separate two fighting serpents, who then coiled themselves around his staff and remained there in balanced harmony.

Another earlier depiction of the medical symbol is the Rod of Asclepius, thought to have no wings and only one serpent. Son of Apollo and the human princess Coronis, Asclepius is the Greek demigod of medicine. According to mythology, he was able to restore the health of the sick and bring the dead back to life.

In one account, Zeus killed Asclepius with a thunderbolt for disrupting the natural order of the world by reviving the dead, while another version states that Zeus killed him as punishment for accepting money in exchange for a resurrection. After his death, Zeus placed Asclepius among the stars as the constellation Ophiuchus, or “the serpent-bearer”.

The Greeks considered snakes to be sacred and used them in healing rituals to honor Asclepius, as snake venom was considered a cure and their skin shedding was seen as a symbol of rebirth and renewal. Which is a good thing to keep in mind the next time you spot a medical alert bracelet featuring the seemingly sinister snakes.

Originally posted on Live Science.

James V. Hayes