I've always had trouble with the cheaper stuff (Bud Light, Miller Lite {ick}, Milwaukee's Best, Pabst, etc) even while I was in remission. Though I used to drink more then was probably advisable in undergrad/grad school.
As I've gotten older and with this flare, I've had more trouble with beer then anything else alcoholic. Only thing that doesn't set me off is Newcastle (very dark, high alcohol) beer and I usually only have 1.
Personally, while in remission, I could drink wine and hard liquor with no ill effects. While flaring, I have trouble with nearly everything alcoholic. Though I just planned to be in the bathroom the day after it happened and sleep most of the following day, if I overdid it.
My advice would be enjoy your birthday. Try something light (Bud, Miller) if you're not feeling great that day. If you want to throw caution to the wind for a day, try a Newcastle, Blue Moon (personal fav!) or Stella Artois. Or a lighter microbrew, like a pale ale. Don't try anything crazy like a espresso infused dark beer...ask you bartender what would be a lighter beer that they recommend. Personally for me, the cheaper the alcohol the worse I feel later...
Just wait until remission before you start to drink more often. Then, keep it in moderation. And as always, be completely upfront with your doctor about
your alcohol consumption and keep taking your meds even if you've had something to drink.