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
All of the following predispose to chloroquine toxicity except? 
Select and explain. 
A. Duration of use > 2 years, B. Cumulative does > 460 gin, C. Daily dose > 250 mg/d or > 3 mg/kg, D. Renal failure
A: Duration of use > 2 years
Answer: A: Duration of use > 2 years 
Explanation: Ans is 'a' i.e. Duration of use > 2 years Risk Factors of Chloroquine toxicity Duration of Disease > 5 years Daily dose Hydroxychloroquine: > 400 mg/day (> 6.5 mg/kg) Chloroquine: > 250 mg/day (> 3.0 mg/kg) Cumulative dose Hydroxychloroquine: > 1000 gm Chloroquine: > 460 gm Age Elderly (>60 years) Physique Sho stature, obese Systemic disease Liver or kidney dysfunction Ocular disease Retinal disease or Maculopathy.