This list for the most part strays away from films that focus specifically on actual drugs and the taking of them (number 5 being the obvious exception). So films like Requiem for a Dream (2000) and Fear and Loathing in Las Vegas (1998) have been left out because the drug-induced state the film puts you in is right along with the characters, making it a very much a subjective look into the experience. I chose the following films mostly because of the highly surrealistic world each creates, often leaving you feeling highly intoxicated. Sometimes it’s an exciting, fun world, and other times it’s a world you are so happy doesn’t actually exist because it’s insanely horrifying.
1) Brazil (1985)
You can pretty much always count on Terry Gilliam for over-the-top bizarre content. Sometimes his movies suffer from style over substance (The Imaginarium of Doctor Parnassus  anyone?), but Brazil manages to effectively create an altogether unsettling and often hilarious world. Between weird baby heads and “Picture me in these!” this movie often has you feeling like you’re flat-out hallucinating.
2) The Great Beauty (2013)
Pretty sure the alternate title for this Oscar winner was “8 ½ Part Two.” That sounds like a snarky dig, but in fact Paolo Sorrentino’s epic successfully captures that oddball, surreal aesthetic that Fellini’s films gained so much notoriety for. The Great Beauty is visually so captivating and leaves many strange and wonderful images unexplained. If the ceiling turning into water doesn’t make you feel doped up, maybe the flock of flamingos or disappearing giraffe will.
3) Tetsuo: The Iron Man (1989)
Perhaps more disturbing than anything else, this classic body horror film will mentally mess you up. Imagine Eraserhead (1977) but Japanese, much weirder, and absolutely terrifying. A guy accidentally hits a metal fetishist with his car, and slowly his own body begins being taken over by metal. The atmosphere of this movie is so disconcerting that by the end of it you’ll likely want to be sober for a very long time.
4) Inland Empire (2006)
Almost any Lynch movie could have made this list (except, perhaps, Straight Story ), but Inland just might take the cake for the most uncanny and disturbing. The film is full of uncomfortable POV shots and fisheye close-ups, making Laura Dern’s nightmarish world all too real. Then, of course, there are the enigmatic bunnies. It only takes about a half an hour to feel like you’re having the worst trip of your life, but buckle down. You have another two and half hours to endure.
5) Enter the Void (2009)
All right, I know this is a movie that is pretty heavily focused on drugs. The main character (if you can call him that) takes a ton of DMT, and just like the examples I referenced earlier like Requiem, you’re given a very subjective experience of what that feels and looks like: twenty minutes of pure shapes and colors. The reason I picked this one, though, is because I think the movie’s more prevalent subject matter is death, and the way Gaspar Noé captures it leaves you feeling at once disturbed and subdued. Not to mention the camerawork in this movie is brilliant, and as you’re floating around Tokyo, drifting in and out of buildings and even human organs, you can’t help but feel like you’ve taken a myriad of different drugs all a the same time.