desensitize vs narcotize

desensitize

verb
  • To cause to become less sensitive or insensitive. 

narcotize

verb
  • To dull the senses of (a person, place etc.). 

  • To make into a narcotic. 

  • To use a narcotic in order to make (someone) drowsy or insensible; to anesthetize, to drug. 

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