I can totally relate to the risk taking trait. I get it. I've owned motorcycles, dirt bikes, spent 7 years living in the Rockies so I could ski the back country (took WAY too many chances there but didn't become a statistic thank god), rope swings, quarry cliff jumps, skydiving, surfing waves beyond my ability, you name it. If it was scary and fun I did it. And of course drinking and drugs were always in the background. Knocked off the drugs pretty young but drinking was downfall.
I really liked Troy's post. Most of my risk taking activities didn't include drinking. That came afterwards to rehash the fun day over drunken conversation. However, I can still do some of these things now. There's a zip line/agility course near my house. Everything is 20+' in the air. I'm going to hit that with my kids.
There are plenty of ways to channel the risk taking urges into sober and safe activities and get plenty of satisfaction (and dopamine). Rollercoasters, tandem sky diving, white water rafting, go cart tracks, waterslides, all come to mind.
If the thrill of risk is really the main driver of picking up the bottle then there are plenty of opportunities out there to score the rush without the booze.
I have no scientific evidence to back this up but I believe there is a connection between risk taking personality types and substance abuse. I've been a risk taker since well before I got into drinking and drugs. I have many friends who are no different.