Vomit Express was recorded in November 1971 and was first made available, twelve years later (February 1983) on "Allen Ginsberg:First Blues", a two-record set (with gatefold cover by Robert Frank) - not to be confused with the Folkways album of the same name - on the legendary John Hammond's eponymous John Hammond Records. That record was later made available in CD format in 2006
It was also part of the Rhino four-CD set, "Holy Soul Jelly Roll - Poems and Songs 1949-1993" (appearing on the final CD - "Ashes and Blues").
Allen's note in the booklet that accompanies that Hal Willner-produced CD boxed-set is as follows:
"These 1971 sessions came about because Dylan had come to hear a poetry reading at NYU's Loeb Auditorium [since demolished and now rebuilt as the Kimmel Center], standing in the back of the crowded hall with David Amram. We were on stage with a gang of musician friends, and Peter (Orlovsky) improvised, singing, "You shouldn't write poetry down but carol it in the air, because to use paper you have to cut down trees". I picked up on that and we spent half an hour making up tuneful words on the spot. I didn't know 12-bar blues. It was just a free-form rhyming extravaganza. We packed up, said goodbye to the musicians, thanked them and gave them a little money, went home, and then the phone rang. It was Dylan asking, "Do you always improvise like that?". And I said, "Not always, but I can. I used to do that with (Jack) Kerouac under the Brooklyn Bridge all the time". He came to our apartment with Amram and a guitar, we began inventing something about "Vomit Express", jamming for quite a while, but didn't finish it. He said, "oh we ought to get together in a studio and do it", then showed me the three-chord blues pattern on my pump organ. A week later in the studio Dylan actually did the arrangement, told people when to do choruses and when to take breaks, and suggested the musicians cut a few endings on their own to be spliced in. "Vomit Express" was a phrase I got from my friend Lucien Carr, who talked about going to Puerto Rico, went often, and we were planning to take an overnight plane a couple of weeks later, my first trip there. He spoke of it as the "vomit express" - poor people flying at night for cheap fares, not use to airplanes, throwing up airsick."
"I'm going down to Puerto Rico/ I'm going down on the midnight plane / I'm going down on the Vomit Express/ I'm going down with my suitcase pain".