The symbol is many-fold. Kundalini The snake sheds it's skin and so is seen as 'coming back from the dead' or rebirth. Two opposing/complimentary forces spiral around a 'pole'. A symbol of lifeforce.

The word naga has ancient multi-faceted meanings. Serpent is knowledge and doctors were known as theraputae.and their knowledge wasn't limited to the medical. The evil connotation isn't present except as it may relate to material knowledge vs spiritual understanding.

As the barber used to shave, give haircuts and let blood.....the barber's pole to this day has red and blue stripes on a pole. Sometimes just the red one.

Some say the Barber of SaVille was a snake. But that's just a conspiracy theory.

It comes from the Bible...

Moses lifted up a serpent on a pole, and the people had to look at it to live. This is a symbol of Christ becoming sin for us on the cross.

John 3:14-15

“And as Moses lifted up the serpent in the wilderness, even so must the Son of man be lifted up: That whosoever believeth in him should not perish, but have eternal life."

Snake Oil

Images and statues of baphomet have a staff with twin snakes

This medical symbol, many thousands of years old, sure does look like a DNA strand.

As @truth_ below said: it is mentioned in the bible where a " single" snake had to be looked up to to be healed. It rather represents the staf of aesculapus.

This imagery is best known as the caduceus. It represents mercury. A totally different animal.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4439707/ https://www.jstor.org/stable/3289465

Quite a number of academics have written about the confusion. And clearly, people eagerly repeat the same.

Hermes, son of Zeus was a messenger of the god’s to the humans, and he carried one such herald’s staff called Kerykeion in Greek or caduceus in Latin. Hermes had a winged cap and winged sandals. His herald’s staff is likewise winged. It is a short rod, with two serpents coiled around it. The serpents’ heads meet just below the wing.

The caduceus has come to represent Hermes and all trades and undertakings associated with him. It also became the astrological symbol for the planet Mercury, named after the Roman counterpart of Hermes, and subsequently its metal namesake. Basically, everything that Mercury stood for is symbolized by the caduceus. Mercury is the Roman god of eloquence, commerce, money making, travel, and thievery. He was also believed to have invented all of the arts.

So, based on the latter, arts as in 7 liberal arts = wisdom.

Big pharma is a snake in the grass open market clinics more choices and get rid of the biggest pyramid scheme in America our health care is a joke we should be able to do may better than this

I think this has something to do with hermes and the later adoption of hermes the messenger