A 38-year-old man with HIV on zidovuvine-based ART presents with fatigue and pallor. Blood tests reveal macrocytic anemia with a hemoglobin of 8.5 g/dL. Which antiretroviral is most likely responsible for this adverse effect?
- A Tenofovir
- B Lamivudine
- C Zidovudine ✓
- D Emtricitabine
Correct answer: C. Zidovudine
Explanation
Zidovudine inhibits mitochondrial DNA polymerase gamma in erythroid precursors, causing macrocytic anemia and occasionally granulocytopenia. It is the classic NRTI associated with bone marrow suppression. Lamivudine, tenofovir, and emtricitabine have minimal bone marrow toxicity. Mycophenolate and valganciclovir are other non-ART causes of marrow suppression in HIV patients.
Reference: Katzung's Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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