aperient vs evacuant

aperient

adj
  • Having a gentle laxative effect. 

noun
  • A laxative, either in the form of a medicine or a food such as asparagus or hops, which has the effect of moving the bowels, or aiding digestion and preventing constipation. 

evacuant

adj
  • laxative 

noun
  • a laxative 

  • something used to clean out an organ system, especially the bowels 

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