After drinking a single small glass of wine, a man with no history of violence becomes suddenly and senselessly violent toward those around him for about an hour, shows none of the usual unsteadiness or slurred speech of drunkenness, and afterward has no memory whatsoever of the episode. What is this?

This is pathological drunkenness: sudden, senseless violence disproportionate to a small quantity of alcohol, without the usual physical signs of drunkenness, lasting around an hour, and followed by amnesia — exactly the pattern the phenomenon's own text describes. It is not ordinary alcohol intoxication, since the amount consumed is far too small to account for this severity of behavioural change, and the usual physical signs of drunkenness are notably absent. It is not an episode of mania, which would not have this specific alcohol-triggered onset and abrupt hour-long course. And it is not a dissociative fugue, which does not typically involve this pattern of violence and specific alcohol trigger.