This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Psychiatry
A psychiatric patient on regular treatment had his routine check-up. His fundus shows the below finding. The most probable drug implicated is ( Pigmented retinal epithelium) 
Select and explain. 
A. Thioridazone, B. Haloperidol, C. Chlorpromazine, D. Clozapine
A: Thioridazone
Answer: A: Thioridazone 
Explanation: Irreversible retinal pigmentation is associated with the use of thioridazine at dosages above 1000mg/day(hence <800/day ) nocturnal confusion is an early sign of this adverse effect. Reference: P.3121 chap. 31.17First-Generation Antipsychotics (Kaplan & Sadock's Comprehensive Textbook of Psychiatry, 9th Edition)