Chloramphenicol is an antibiotic that is used to treat a variety of bacterial infections. It works by inhibiting the growth of bacteria, making it effective against certain serious infections, especially those caused by Haemophilus influenzae and Streptococcus pneumoniae. Originally derived from the bacterium Streptomyces venezuelae, chloramphenicol is available in both oral and intravenous forms. While it can be very effective, it is generally reserved for severe infections due to potential side effects, including the risk of aplastic anemia, a serious condition affecting blood cell production.