Azidothymidine (Zidovudine), commonest side effect is
Hyperuricemia
Pancreatitis
Peripheral neuropathy
Macrocytic anaemia
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.