Walter Benjamin experimented with hashish, opium, and mescaline (as, it now occurs to me, I have also); I believe he recorded his impressions in journals, but various people have gathered these entries and concocted various and variously titled essays as if they were a work completed by Benjamin.
Wanting to give an example of his prose, here is one of his journal entries written after using hashish and going to a restaurant in Marseilles; it strikes me as amusing and authentic:
First I ordered a dozen oysters. The man wanted me to order the next course at the same time. I named some local dish. He came back with the news that none was left. I then pointed to a place in the menu in the vicinity of this dish, and was on the point of ordering each item, one after another, but then the name of the one above it caught my attention, and so on, until I finally reached the top of the list. This was not just from greed, however, but from an extreme politeness toward the dishes that I did not wish to offend by refusal.
[Also] I have forgotten on what grounds I permitted myself to mark the beat [of the jazz music heard from down the street] with my foot.