anxiolytic vs ataractic

anxiolytic

adj
  • That reduces anxiety; tranquilizing 

noun
  • A drug prescribed for the treatment of symptoms of anxiety. 

ataractic

adj
  • That has a tranquilizing effect. 

noun
  • A drug that is used to tranquilize; a tranquilizer. 

How often have the words anxiolytic and ataractic occurred in a corpus of books? (source: Google Ngram Viewer )