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: Social & Preventive Medicine
Ethambutol is associated with 
Select and explain. 
A. Red-green colour blindness, B. Red-blue colour blindness, C. Blue-green colour blindness, D. Yellow-green colour blindness
A: Red-green colour blindness
Answer: A: Red-green colour blindness 
Explanation: Ethambutol may cause ‘optic neuritis’ (ocular toxicity): 463 National Health Programmes, Policies and Legislations in IndiaReview of Preventive and Social Medicine
It may lead to ‘red-green color blindness’
Patients may thus develop ‘blue vision’
Thus it is contraindicated in children < 6 years age, as they may not be able to report any deterioration of color vision.