I was at a party ~25 years ago and there were kittens running around. At some point, it became unclear to me which of the kittens were real. Some definitely were, but I was sometimes unsure if what was running around me was actual kitten or hallucinated kitten. That's probably the furthest gone I'd been and I still was able to understand that this was the situation. I also did a lot of stuff back then (and don't touch anything these days).