Last edited 03/2021 and last reviewed 10/2022

Chloramphenicol is an antibacterial and antirickettsial which should be reserved for the treatment of severe life-threatening infections due to H. influenzae and typhoid fever since when given parenterally it may be toxic .

Chloramphenicol acts to inhibit peptidyl transferase on 70S ribosomes such that it prevents peptide bond formation.


  • FBC needed before and during treatment on a regular basis
  • neonates - grey baby syndrome
  • beware interactions - see current issue BNF
  • avoid repeated course and prolonged treatment
  • reduce doses in hepatic or renal failure

Contra-indications include:

  • pregnancy and breast feeding
  • porphyria

Routes of administration:

  • oral:
    • capsules
    • suspension
  • i.v. injection
  • i.v. infusion

Check the Summary of Product Characteristics before prescribing