Which antibiotic is associated with aplastic anemia?

Which antibiotic is associated with aplastic anemia?

• A. Clindamycin
• B. Chloramphenicol
• C. Amoxicillin
• D. Erythromycin

Answer: (B)

Aplastic anemia occurs when the bone marrow fails to produce enough blood cells, leading to pancytopenia. Some drugs can trigger this rare, idiosyncratic reaction, and among antibiotics, chloramphenicol has the strongest historical association with it. The risk with chloramphenicol is not tied to the dose or duration in a predictable way; it can occur even at standard therapeutic levels and after varying lengths of exposure. Because it can irreversibly suppress bone marrow, stopping the drug promptly and providing supportive care are critical. Clinically, this presents as fatigue, easy bruising or bleeding, and increased susceptibility to infections due to low red cells, platelets, and white cells. A bone marrow examination would show a hypocellular marrow with Holliday-like fatty replacement, consistent with aplastic anemia. Other antibiotics in the list can have important side effects—such as clindamycin’s association with pseudomembranous colitis, or amoxicillin and erythromycin causing mainly gastrointestinal upset or hypersensitivity reactions—but they are not classically linked to aplastic anemia in the way chloramphenicol is.

Aplastic anemia occurs when the bone marrow fails to produce enough blood cells, leading to pancytopenia. Some drugs can trigger this rare, idiosyncratic reaction, and among antibiotics, chloramphenicol has the strongest historical association with it.

The risk with chloramphenicol is not tied to the dose or duration in a predictable way; it can occur even at standard therapeutic levels and after varying lengths of exposure. Because it can irreversibly suppress bone marrow, stopping the drug promptly and providing supportive care are critical. Clinically, this presents as fatigue, easy bruising or bleeding, and increased susceptibility to infections due to low red cells, platelets, and white cells. A bone marrow examination would show a hypocellular marrow with Holliday-like fatty replacement, consistent with aplastic anemia.

Other antibiotics in the list can have important side effects—such as clindamycin’s association with pseudomembranous colitis, or amoxicillin and erythromycin causing mainly gastrointestinal upset or hypersensitivity reactions—but they are not classically linked to aplastic anemia in the way chloramphenicol is.