This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
Gray baby syndrome is caused by - 
Select and explain. 
A. Penicillin, B. Chloramphenicol, C. Rifampicin, D. Erythromycin
B: Chloramphenicol
Answer: B: Chloramphenicol 
Explanation: Ans. is 'b' i.e., Chloramphenicol o Chloramphenicol causes gray baby syndrome in premature neonates due to blockade of electron transpo in liver, myocardium and skeletal muscle. Remember o Chloramphenical is the most common cause of aplastic anemia. o Tetracyclines are the most common cause of superinfections.