Why are Cosmas and Damian patron saints of barbers?

We often do not know why saints may have a particular patronage. Sometime in history a group of barbers evidently petitioned the Vatican for permission to use Cosmas and Damian as their patrons and it was granted. Cosmas and Damian were twin brothers and were physicians. In ancient times barbers often did minor surgical procedures and this is still commemorated today with the traditional barber pole with red and blue stripes. Bleeding of sick patients was a common practice used in early medicine and the barber pole represents a limb of a bleeding patient.