Step 1: Read the clues. A chronic alcoholic who stopped drinking about 3 days ago now has confusion (irrelevant talk), tremor, and sweating. This timing and symptom cluster points to severe alcohol withdrawal.
Step 2: Name the syndrome. Delirium tremens, also called alcohol withdrawal delirium, is the most severe form of ethanol withdrawal. It features altered mental status (global confusion) and autonomic hyperactivity (sweating, tachycardia, tremor), and classically peaks around 48 to 96 hours after the last drink.
Step 3: Mechanism. Chronic alcohol enhances inhibitory GABA activity and blocks excitatory NMDA receptors. On withdrawal, GABA inhibition falls and NMDA-mediated excitation rises, producing tremor, diaphoresis, tachycardia, anxiety, and in severe cases seizures.
Step 4: Why the distractors are wrong. Korsakoff psychosis is a chronic amnestic state from thiamine deficiency, not acute confusion with autonomic surge. Post-acute withdrawal and discontinuation syndromes are milder and not characterised by acute delirium.