penicillin vs sulfa drug

penicillin

noun
  • Any of a group of narrow-spectrum antibiotics obtained from Penicillium molds or synthesized, that have a beta-lactam structure and are active against gram-positive bacteria and used in the treatment of various infections and diseases. 

  • A blue mold of the genus Penicillium that produces penicillin. 

sulfa drug

noun
  • Any of a group of antibiotic drugs structurally related to sulphonamide, tending to be bacteriostatic rather than bacteriocidal. 

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