A Keg of beer is a large barrel of beer which can be drunk. When you drink it, it says, "You chug the keg. You feel reinvigorated... ...but extremely drunk, too." Your character raises the keg above their head and chugs the entire Barrel. It temporarily lowers Attack by 40 and raises Strength by 10, as well as causing the perspective of your screen to swing back and forth for a minute, as if your character is drunk. (This can be stopped by teleporting or doing an emote.) It isn't a good idea to drink this in a combat area, as it makes melee attacks much less accurate.
Kegs of beer are dropped by Dagannoths, Level 48 Black guards in Keldagrim, Chaos dwarf hand cannoneers in the Chaos Dwarf Battlefield, Rock crabs, and Market guards in Rellekka. It can be bought in the Rellekka Longhall for 325 coins, provided that the player has completed The Fremennik Trials quest. It can also be bought from the merchant north of Ardougne.
If you use this item in conjunction with a few doses of Restore potion, it can act as a cheap, one-use alternative to a strength potion with the added bonus of healing you. In fact, if your strength level is below 70 and you don't care about accuracy or can recover your levels easily, it becomes superior to a strength potion.
Note: When in dangerous areas combating high-level opponents, food and super strength potions are more reliable than kegs, which take a long time to consume and require you to carry restore potions instead of more food or potions.
A player drinking a Keg of Beer.
Trivia
Beer kegs are also one of the few edible items that have unique consumption icon. Unlike most drinks,when a player drinks a beer keg they can be seen tipping the barrel back with both hands.
When the player attempts to drink a keg of beer whilst on the fishing trawler, they will receive a message saying "With my sea sickness? You must be joking!"
On drinking, the entire keg disappears from the players inventory.
The keg of beer provides better strength boost than a super strength potion until level 34
Kegs of beer are sometimes used in movies due to their animation.