Gastric Byp question..............?

I'm 6'0 and a little over 300 pounds. I got this big I guess from medications I used to take becayse I was always built much thinner than i've been. I used to be able to work out and everything, but i'm having trouble. I'm still young, but I just can't do what I did because of my weight. I guess my Q is am I a candidate from Gastric Byp and/or what does it take to be one. Thanks.