I'm a New York-based finance professional (former investment banker turned private equity investor) with a background using a wide variety of drugs, but mostly heroin. Besides heavy drinking and rare cocaine use among younger peers (analysts), I didn't see a lot of substance abuse. I often felt quite alone, especially in using my drugs of choice.
I started using heroin right after I graduated high school, and used it throughout undergrad, as it honestly helped me get better grades by quieting the turmoil in my mind. I experimented with suboxone and methadone after graduation, and was using a mix of methadone, Provigil (a stimulant, to counteract the drowsiness from the methadone), and alprazolam (to take the edge off the Provigil) when I started my first banking job in NY. I was let go for nodding off at work.
At my next job, I started using heroin again after a brief period being drug-free, and started injecting. I had a short-lived job at another investment bank, where I injected heroin, cocaine, or a mix of both pretty much all day at work, even setting up a way to do it at my desk discreetly to avoid having to get up and go to the restroom so often. That job obviously did not last long.
I used like that for a few months, got another job at a bank, and stopped those drugs, but continued to seek prescription painkillers sporadically, and drink to take the edge off. I managed to keep it together for that job, but my overall demeanor made it tough to really succeed. Before starting in private equity, I got sober (no controlled substances or alcohol anymore), and have been sober since mid-2012. It's been the biggest and best decision of my life.
I used to think I was perhaps one of just a handful of finance professionals with as intense background in hard drugs, but I'm coming to see there are too many of us out there.