Trippy drug, for short

LSD

This hallucinogenic compound was famously studied in 1960s psychological experiments and shares its initials with a common measure of money.

Trippy drug, for short" hints at a well-known hallucinogenic substance. The word "trippy" is slang for something that causes vivid hallucinations or alters perception, which directly points to LSD (lysergic acid diethylamide). The clue adds "for short" to signal that the answer is an abbreviation, not the full chemical name. LSD is a common shorthand in pop culture for this psychedelic drug.