1. Howard J. Balbi, MD* 1. *Director, Pediatric Infectious Diseases, Good Samaritan Hospital Medical Center, West Islip, NY; Associate Professor of Pediatrics, State University of New York at Stony Brook, Stony Brook, NY After completing this article, readers should be able to: 1. Explain why chloramphenicol no longer is the drug of choice for any infection. 2. Name those conditions for which chloramphenicol may be an effective alternative therapy. 3. Discuss why serum concentrations of chloramphenicol are erratic, especially in those who have liver disease. 4. Recognize the major adverse effects of chloramphenicol. 5. Explain why serum concentrations of chloramphenicol are affected by the concomitant use of certain drugs such as phenytoin, rifampin, or phenobarbital. Chloramphenicol is an antimicrobial agent used rarely today in the United States because of its associated adverse effects (Table 1). At one time it was hailed as a highly effective, broad-spectrum agent against many gram-positive and gram-negative bacteria, spirochetes, chlamydiae, and rickettsia. Chloramphenicol had a major role in the treatment of meningitis caused by Haemophilus influenzae , Streptococcus pneumoniae , and Neisseria meningitidis because of its bactericidal activity against these organisms and the ability to achieve high concentrations in the cerebrospinal fluid. As is the case with more recent “miracle” antimicrobials, perhaps chloramphenicol was overused since its discovery in 1947. This may have led to the development of resistance and increased reports of adverse events. Today there are many alternative agents that have greater safety profiles, but chloramphenicol remains a useful antimicrobial agent. This review addresses the clinical indications for chloramphenicol usage, spectrum of antimicrobial activity, pharmacokinetic properties, bacterial resistance, and major adverse effects. | Dose-related | || | | | Not Dose-related | | | Table 1. Adverse Effects Chloramphenicol is produced synthetically, but it was isolated originally from the organism Streptomyces venezuelae found in soil and compost. Production of the oral preparation, chloromycetin palmitate, was …