Fatal Aplastic Anemia Following Chloramphenicol (Chloromycetin®) Administration

Reports of serious toxic effects following administration of chloramphenicol have been few. After the chemical structure of this antibiotic became established, the presence of a nitrobenzene radical caused some apprehension in regard to potential toxicity.1The early toxicity studies on animals2and man3led to the conclusion that chloramphenicol is of low toxicity. Later hematological observations on animals following administration of chloramphenicol by various routes were believed to reveal no deleterious effects that could be ascribed to the drug. Smith and co-workers4found that anemia developed following intramuscular administration of chloramphenicol to dogs in a dosage of 0.05 to 0.1 gm. per kilogram of body weight. No change occurred in the total or differential white blood cell count. Anemia did not follow oral administration. Gruhzit and associates,5using dogs, administered chloramphenicol by different routes for as long as four months in a dosage of 0.1 to