Yeah, it's not particularly fun when it hits hard. I got on a night bus in London once I had landed, and kept teetering between chatting up a geisha girl in a park, and sitting next to a tramp who kept trying to start a conversation with me.
In my hallucination state, the world was bright, colourful and the girl was wonderful. Words rolled off my tongue like crystal clear water trickling down a quaint little brook.
In my reality state, the tramp smelt of Diamond White cider and Pedigree Chum. The bus driver was by FAR the roughest bus driver since the day before forever, and the world around me swirled like a flushing toilet. It was just a mixture of the city skyline and dodgy kebab shops.
And then, occasionally, I'd bump into Noel Edmonds. (Was it dream or reality? I still don't know.)
Anyway, I don't even remember going to bed. I just know that I woke up in it.
Try it. See if you can beat my 3 day record.