I'm voting yes for the Lost Weekend.
The movie has some issues, and I agree with Amy that this is certainly not Billy Wilder's best, but I still think it deserves to be in the Canon. Because while the movie could be a tad melodramatic at times, reaching Reefer Madness territory once or twice, overall it's a gut-wrenching and honest look at the horrors of addiction. It was super progressive for the time, and discusses addiction in a manner that stupid people in 2016 sometimes still can't wrap their minds around. I also love how it could sometimes look like a horror movie, even having the Theramin in the soundtrack occasionally, like alcoholism is a monster slowly destroying his life.
And man do I love the scene where he tries to sell his typewriter for booze money. How harrowing. He's considering selling his tool to write, to feed his drinking habit which he claims helps him write. What a crazy vicious cycle. This was my first time checking out the movie, and while there are certainly issues, and it's not Wilder's strongest, I really liked it, and I think it certainly belongs in the Canon.