I went a little too hard one night and put myself in the hospital for half a week with alcohol induced acute pancreatitis (which has been known to kill people in a rather painful manner, unfortunately). Apparently hard liquor now has the ability to trigger another round of pancreatitis if I indulge too heavily, but beer is diluted enough that it doesn't have the same effect... perhaps? I'm a little fuzzy on the details, to be honest.
They made it sound like I now have an allergy to alcohol, but I don't quite understand the how and why.
It took me a very long time to find one I liked. We have some exceptionally bad beer in Canada... it's hard to decipher the crap from the decent stuff. Most of it is over carbonated and gets a person hung over before they get drunk.