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
Azidothymidine (Zidovudine), commonest side effect is 
Select and explain. 
A. Hyperuricemia, B. Pancreatitis, C. Peripheral neuropathy, D. Macrocytic anaemia
D: Macrocytic anaemia
Answer: D: Macrocytic anaemia 
Explanation: Ans. is 'd' i.e., Macrocytic anaemia "The most common adverse effect of zidovudine is myelosuppression, resulting in macrocytic anemia (1-4%) or neutropenia (2-8%)". So most common side effect of zidovudine is neutropenia (2-8%) followed by macrocytic anemia (1-4%). Other side effects are - nausea, anorexia, headache, insomnia, abdominal pain, myalgia, malaise, fatigue, myopathy, lactic acidosis, hepatomegaly with steatosis, convulsions and encephalopathy.