stupefactive vs tranquilizer

stupefactive

adj
  • Inducing stupor; making drowsy; stupefacient. 

tranquilizer

noun
  • That which tranquillizes or soothes. 

  • A drug used to reduce anxiety or tension. 

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