Alcohol is horrible for it's calorie content...and how it slows down the metabolism, which is deadly for those with a slow metabolism. If your diet and exercise are superb you might be able to get away with having a few drinks on a Friday night. But if Friday turns into Saturday, Sunday, Thursday, etc. it will be VERY difficult to lose much weight.
I rarely drink alcohol. Because I don't drink much, it's effects are magnified on me. Two weeks ago, I had four beers at the local bowling alley, catching a Steeler game in LA. I didn't make me drunk, but made me fatigued and that meant I missed my cardio for the day. I decided right then and there that I could do without beer with my football games and have watched the past two games with diet coke.