How cocaine crushed my trading skills

Turney Duff chronicled the spectacular rise and fall of his Wall Street career, which included heavy cocaine use, in his book, "The Buy Side." Now five years sober, he shares his insight about how cocaine use crushed his trading skills—and cost him and his firm millions.

I loved cocaine. Part of me still does. I also loved trading stocks. The rush of euphoria was very similar. Some may write off cocaine use as a party enhancer or coping mechanism for such a high-stress job, but in fact, it's a trade killer. And I wasn't alone.

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Recently, a study came out from a team of researchers at the Icahn School of Medicine at Mount Sinai that showed cocaine use leads to bad decision-making. They recorded the brain activity of 50 cocaine users and 25 nonusers while they played a gambling game. The scientists were specifically examining the signals in the brain that help humans predict the possible rewards and punishments that might result from a decision.

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It may seem obvious that cocaine use leads to bad decision-making, but most people don't realize that it transcends to all areas of your life. And it's a lesson learned after countless mistakes. And I'm not talking about one night — I'm talking about a cumulative effect over a period of years.

The most insidious part of addiction is not realizing that this is happening.

I actually had a fairly successful career on track trading stocks before I ever tried cocaine. I understood how to evaluate risk better than most of my peers. I knew how to make money. And for most of my former bosses—that's all that mattered. I made good decisions, I knew how to cut losses and I never crossed my fingers.

That is until I started doing cocaine.

It's not like you rip one line and then all of a sudden your life falls apart. For me, I started to have what I thought was more fun at night, which resulted in less success during the day. I was still making money, but not making great decisions all of the time. My formula for success started slipping away from me. It took about two whole years before the wheels started to fall off. Then I started losing money and making very poor choices in and out of the office.

During my years of struggling with addiction, my trading suffered. One of my first seven-figure losses came because I'd lost focus and attention to detail. I just didn't do the clerical part of my job over options expiration. And when I came into work on Monday, I learned that it cost our firm over a million dollars. And in 2009, I lost hundreds of thousands of dollars personally. I was stubborn. I was adamant that the market shouldn't be rallying as much as it was. I was short, stayed short and doubled down. And the entire time I knew I was breaking a cardinal rule of trading: Don't fight the Fed.

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Since writing my memoir, I've had numerous parents of aspiring traders and recent graduates ask me if cocaine use is endemic on Wall Street. The answer is no—it's not part of the job description, but it is a fairly large rabbit hole that is easily to fall into. That first cocaine high is so good; it's hard to imagine never doing it again. And that's when the trouble begins.

I'm sure some will say I couldn't handle my coke and booze and they're right. But my ability to function at my job was still impaired even when I was able to wake up, shower, suit up and make it to work on time. Cocaine limited my ability to manage risk even when I wasn't on cocaine.

I don't think financial drug use is one of those chicken-or-the-egg-type things. The pressure of the job doesn't create the need for the drug. But the need for the high of the drug does help enable not feeling the feelings from the job. Wall Street attracts a certain type of personality, but that does not mean they're drug addicts or alcoholics. Most people who enter this industry love the excitement, the high intensity and big stakes of the job. The temptation of cocaine is appealing to some to help numb the pressure – and the losses.

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Although finding cocaine on Wall Street is as easy as finding weed at a Grateful Dead concert; you still have to look for it. There's actually a much smaller percentage of people using on the street than you think.

But does it go on? Absolutely.

The two words that best describe my out-of-control cocaine addiction are "numb" and "escape." I didn't want to feel and or I wanted to run away from feeling what I was feeling. At the very core of every addict is the premise of not being able to make good decisions. There's a lie we keep telling ourselves and believing. Somehow, some way, the next time will be different. We can control it. We'll only do a couple of lines or we'll shut it down at midnight — it never happens. And this crossed over to work and life decisions as well.

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At some point I lost my ability to make good decisions. It's not like I decided to start playing human Frogger on the Long Island Expressway, but there were no self-imposed checks and balances to my emotional and physical state.

This is the section where I talk about what I lost to cocaine addiction, but the truth of the matter is that I didn't lose anything — I gave it all away. There were multiple jobs, a house, savings account and the jeopardy of my relationship with my daughter. In order for me to continue down my road to recovery, I need to be accountable for my past actions. On paper you'd think I'm in a much worse situation than I was six years ago, but I've never been happier. What I've gained from being sober outweighs giving up the material things.

Fact: I'm a much better trader, father and friend when I'm sober from drugs and alcohol. When I was on, coming down from or in search of cocaine there was zero to little risk-reward brain analysis going on in my head — it was looking for the reward and didn't care much about the risk.

I don't think you can blame cocaine for all of Wall Street's misbehavior and poor choices, but it's clearly not helping.

Commentary by Turney Duff, a former trader at the hedge fund Galleon Group. Duff chronicled the spectacular rise and fall of his career on Wall Street in the book, "The Buy Side," and is currently working on his second book, a Wall Street novel. He is also featured on the CNBC show, "The Filthy Rich Guide." Follow him on Twitter @turneyduff.

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