I feel like ever since an adult grasped the original Advanced Dungeons and Dragons manual, there has been drinking and D&D. At every game, peeps bring snacks and beverages and dice and supplies, and as we age up, those snacks and beverages often upgrade from chips and soda to wings and mead (I know, many of you expected beer, but I can't drink that junk). The addition of alcohol to a gaming setting can have a number of interesting effects, from breaking down walls to accelerating belligerent behavior to increasing fun flow to failing to follow anything during their turn but hyperfocused on playing everyone else's character... There are a few things I keep in mind whenever we introduce this type of energy into our tabletop setting.
1) This is a Social Gathering
No, seriously. For my players, this is a social thing. They're coming to play, enjoy themselves, enjoy the cooperative company of others. Also, these are always adults over the age of 21. Adult language can be used, mature themes explored, but most of all, they can make their own decisions when it comes to the level of drunk they're pursuing. And it takes experience to get the balance right.
I recall a specific game, our first 21+ game, where a good friend of mine showed up without eating much that day, then proceeded to pound down 4 drinks, fell asleep halfway through the session, woke up enough to get the killing blow (dude), then we hung out with him until he was good enough to drive (no matter how long that would take). We talked through all the poor decisions that led to that debacle, made sure he was safe going home, and the next time, he learned about EATING FOOD DURING THE DAY. Yeesh.
We've since grown up collectively, and even in that experience, the community of the party rallied around that player to help him stay safe, and made absolutely sure that he was alright during and after play had concluded. Why? Because we're adults too, we understand, and we're not jerk-faces. :)
There's going to be an ebb and flow to the evening, depending on how much people have consumed and by what rate, and everyone's tolerance is different. It will flow organically, just like any other social gathering. And everyone can choose the rate at which they partake (or don't partake).
2) Adding Energy To A System
Speaking of not partaking, I don't drink when I DM. It's tempting as hell at a 21+ event, but this is my job, and I'm never breaking that rule. Even if it's for a casual home group, I don't feel comfortable crossing that line. And it's because I need to be the steady in the room. Even-tempered, steady keel, arbiter of the rules and mainstay of the session. I am the constant, and that keeps the fantasy rolling. It also ensures that I don't miss as many details, so I can stay consistent.
My partner in crime, John Tanaka, said it best: "Alcohol adds energy to a system." Now, often the type of energy is dependent upon how each player responds to alcohol. Some will become louder, others more silly, and others more mellow; plus a full oscillation between as levels of buzz rise and fall. Mitigating this is actually much easier than you think, though.
First, meet your players with patience. It's okay if you have to repeat yourself or explain something differently (just as with any table), even if you feel you're doing it a lot. Some people get faster when they drink, others slower, and all in different ways. Just try to meet them where they are first, and guide them up to the level of understanding you need them at; don't demand that they leap to you - remember, drunk people don't move so well - take their hand and guide them up your well-labeled steps to the Landing Of Understanding.
Second, try your best to end on time. Alcohol's end result is BEDTIME, and the further you push beyond the agreed-upon end, the harder the time your players will have. And it's okay if the end time is 2am, if everyone knew going in...just don't go to 4am instead. A pre-determined end helps those adults plan accordingly, and if we push beyond that, people start shutting down. If you end a little ahead of schedule and everyone's satisfied? BONUS GLUTEN-FREE BROWNIE POINTS WITH CHOCOLATE CHIPS.
Third, stay consistent. Like I said, I'm the anchor for the session. All my wayward ships need a lighthouse, right? If I waver too much, I can sacrifice the social contract that we all bought into the game at the start. I need to make sure that my conduct is consistent from the start of the session to its close, even if my players fluctuate. That gives them a clear expectation to look toward at every moment of the session; they can trust me to be empathetic, understanding, but firm, and consistent. :)
And that's all I can say for now. Adults can make their own decisions as to the level of buzz they want to ride, and that changes from individual to individual, night to night. The only things I can do is maintain my own control level, be consistent, and stay kind. My players will sort themselves out as long as I keep a good table with clear expectations. Speaking of which...
See you over there.
Professional Game Master musician, music teacher, game designer, and aspiring fiction author.