An alcoholic is brought to the casualty, 3 days after he quit alcohol, with the complaints of irrelevant talking. On examination, he is found to be disoriented to time, place and person. He also has visual illusions and hallucinations. There is no history of head injury. The most probable diagnosis is:

This patient in the question who is a chronic alcoholic is showing features of delirium tremens, which typically appears after 3-4 days of abstinence from alcohol (24 hours to 7 days). Ref: CURRENT Diagnosis and Treatment: Emergency Medicine, 7th Edition, Chapter 37 ; CURRENT Diagnosis and Treatment: Psychiatry, 2nd Edition, Chapter 14