Ancestry of Antibiotcs: An overview

Antibiotics are classified based on their chemical structure and mode of action. A similar level of effectiveness, toxicity and side-effects is rendered by the antibiotics of same structural group. Broad spectrum antibiotics are effective against a broad range of microorganisms in comparison to narrow spectrum antibiotics. Bactericidal antibiotics kill the bacteria whereas bacteriostatic antibiotics halt the growth of bacteria. A very interesting post by Fabio Cacchiata in which he classified antibiotics in a very nice way with full of details.


How Do Antibiotics Work?

Various types of antibiotics work in either of the following two ways (as mentioned in the above image):

  1. A Bactericidal antibiotic kills the bacteria generally by either interfering with the formation of the bacterium’s cell wall or its cell contents.Penicillin, daptomycin, fluoroquinolones, metronidazole, nitrofurantoin and co-trimoxazole are some example of Bactericidal antibiotics.
  2. A Bacteriostatic antibiotic stops bacteria from multiplying by interfering with bacterial protein production, DNA replication, or other aspects of bacterial cellular metabolism.Some Bacteriostatic antibiotics are tetracyclines, sulphonamides, spectinomycin, trimethoprim, chloramphenicol, macrolides and lincosamides.