While hallucinating, Jane asks Lisbon for water, and calls her "Bella Donna", which means "beautiful woman", in addition to being the drug.
Chasing a rabbit into a beautiful garden has a strong similarity to Alice in Wonderland, which also involves a caterpillar (a larval butterfly, which Jane sees) sitting on a mushroom ingesting hallucinogens from a hookah, and a mad tea party.
The location standing in for the front of the hospital where Jane nearly steals an ambulance after having his stomach pumped is the same location as Yuri Bajoran's helicopter company from "Red Hot" (season 3 episode 7)