It may be difficult to ascribe a therapeutic value to the serpent. In Greek mythology the snake had magical powers associated with prophecy, dreams and healing. The Greeks also believed that the Gods appeared on earth in the guise of serpents, Greeks, Egyptians and Hindus venerated the snake as the companion of the gods. In Bible when Moses in the wilderness at the Lord’s command, made a bronze replica of a snake and attached it to the top of a pole, anyone who was bitten by a snake lived if he simply looked at it.
In ancient times a species of harmless yellow snakes, now extinct, flourished in the region of Epidaurus in Greece. These reptiles were quite tame. Trained to lick the affected parts of the sick, they were used to being handled. At Epidaurus there was Asclepeion, the temple of Aesculapius’ cult.
In 293 BC when a plague was raging in Rome, its citizens asked that a mission be sent from the Asclepeion Temple. As its transport sailed up the Tiber, a sacred snake slid from the deck and swam ashore. So great was the popular belief in the healing power of the Sacred snakes that a temple to Aesculapius was built upon the spot where the snake landed.
By all accounts the daughters of Aesculapius, Hygeia, the goddess of health and panacea fed the sacred snakes and Aesculapius himself was seldom depicted without a rod with a sacred snake entwined about it. As a matter of fact, snake entwined staffs considerably predate Aesculapius.
The caduceus, modern symbol of medicine, a rod entwined with two snakes, though often confused with the Aesculapius symbol is associated with Mercury, a Latin god of commerce and gain. It is thought that the caduceus originated as an Assyria Babylonian symbol representing a god some of whose functions were medical and was carried over from the earlier civilization into that of Greece and Rome.
In ancient Egypt the single snake motif appears to have symbolized the gift of life and sovereignty and the intertwined serpent motif was for the most part associated with Fertility.
In the 13th & 14th centuries, the European crusaders who went to war against the Arabs acquired some of their enemies’ knowledge. With it they brought about the intellectual awakening of Europe, known as the Renaissance. The caduceus was not adopted as a medical symbol until the Renaissance, when pharmacists and chemists were interested in alchemy, a science closely associated with Mercury, both the god and the planet and with the metal named after him (Mercurius Philosophorum).
Since in the 16th and 17th centuries the domains of pharmacy, chemistry and medicine were not yet strictly demarcated and overlapped to some extent, the caduceus attributed to Mercury, came to be regarded as a medico pharmaceutical emblem.
There is also an illusion about the origin of the medical symbol. In Dracunculiasis the guinea worm is slowly withdrawn by winding it around a match stick from its site of predilection, the subcutaneous tissues of man. The matchstick with the guinea worm wound around it is analogous to the Asclepeion staff and misconceived to be the cause of origin of the medical symbol.