A Drug/Alcohol concoction created by comedian Doug Stanhope. The instructions for creating a Xanadoo were first explained by Stanhope on the "The Opie and Anthony Show" sometime in 2007 (or possibly 2008).
A Xanadoo consists of:
Equal parts Xanax and Psychedelic Mushroom caps, ground (usually with a coffee grinder), and poured into Jagermeister shots.
Aside from Stanhope himself and maybe a few unreported cases, the effects of a Xanadoo are largely unknown. Most likely they are (at least) a combination effects from all of its ingredients. I.E. tripping, relaxation, euphoria, blurred vision, and coordination problems.
ThePersonWhoTalks1: What's a Xanadoo?
ThePersonWhoTalks2: Did you even read the definition?
ThePersonWhoTalks2: Look it up on Urban Dictionary, fag.
ThePersonWhoTalks3: Never consume a Xanadoo.
ThePersonWhoTalks4: Yo bro! You wanna try a Xanadoo?
ThePersonWhoTalks5: DUDE, TOTALLY!!1!!1