Alcohol is a hallucinogenic drug.

Alcohol-related psychosis is a secondary psychosis with predominant hallucinations occurring in many alcohol-related conditions, including acute intoxication, withdrawal, after a major decrease in alcohol consumption, and alcohol idiosyncratic intoxication. Alcohol is a neurotoxin that affects the brain in a complex manner through prolonged exposure and repeated withdrawal, resulting in significant morbidity and mortality. Alcohol-related psychosis is often an indication of chronic alcoholism; thus, it is associated with medical, neurological, and psychosocial complications.

This is in response to an ignorant commenter here.