Hunter S. Thompson said this quote

Hallucinations are bad enough. But after awhile you learn to cope with things like seeing your dead grandmother crawling up your leg with a knife in her teeth. Most acid fanciers can handle this sort of thing. But nobody can handle that other trip-the possibility that any freak with $1.98 can walk into the Circus-Circus and suddenly appear in the sky over downtown Las Vegas twelve times the size of God, howling anything that comes into his head. No, this is not a good town for psychedelic drugs.