How was Charles Richet awarded the Noble Prize in Physiology or Medicine?

Name: Charles Richet.
Country: France.
Date of Birth: 25 August 1850.
Died: 4 December 1935.
Education: University of Paris.
Subjects Of Study: Allergy anaphylaxis.
Known as: the Physiology of respiration and digestion.
Noble Prize Year: Nobel Prize for Peace in 1913, in recognition of his work on anaphylaxis.