In Greek mythology, the centaur, Chiron, was wounded by Hercules. Though he was immortal, it is said that he invented medicine in order to heal himself. He taught Asclepius the art of healing, which became the source of all divine medical knowledge among the Greeks. Chiron was also the teacher of the hero, Achilles, who was thought to have had some special medical knowledge.
"...But save me. Take me to the ship, cut this arrow out of my leg, wash the blood from it with warm water and put the right things on it - the plants they say you have learned about from Achilles who learned them from Chiron, the best of the Centaurs."
The Iliad of Homer, Book XI