Instead of leaving a fresh wound open, Theodoric closed it with sutures, thus avoiding purulency. He was criticised sternly by Guy de Chauliac as a copyist and plagiarist probably because he did not adhere to Galen's teachings.
Theodoric wrote: For it is not necessary that pus be generated in wounds -- no error can be greater than this. He also used an anesthetic concoction for his surgical patients, composed of a mixture of opium, hyoscyamus, mulberry juice, lettuce, hemlock, mandrake and ivy. It was used both as an inhalent and a drink.