Beer is an item in Duke Nukem Forever.
Drinking beer makes Duke tougher and reduces damage by 75% for a short period of time, although when the player consumes a beer Duke becomes drunk and his vision becomes very blurry. There is also a slight slow motion effect, but not enough to really change gameplay, besides humorously making sounds deeper. Beer in DNF is in a large 40 oz. can. Duke can carry beer in his inventory to drink later.
To unlock some trophies/achievements, drink beer for the first time, drink beer and take steroids together, or drink all 8 beers in the strip club.