(Years ago at least) Beer was still in the USP. It is used to encourage urination and improve attitude. The usual dosage is two. (Sorry, no cite. I used to date a pharmacist.)
As I am the webmaster of http://www.dextromethorphan.ws and http://www.coricidin.org this one is right up my alley. 
By and large, and for the most part, you are right. But not totally. While you may may have heard of “robotripping” or use of other DXM containing preparations just recently, this is hardly anything new. I have an MP3 on my site of a Patti Smith song from 1974 where she sings “I lay back. I get my nerve up. I take a swig of Romilar.” Romilar was the main cough syrup containing DXM used recreationally long ago. I have various historical citations of recreational DXM use back all the way into the 1960s. Tripping on DXM goes way back. It even predates LSD, because DXM containing cough syrups were available for use as a psychedelic drug before LSD became a common street drug.
Pharmacists have known about the recreational potential of DXM since it was introduced in the 1960s. There have been cases that far back where pharmacists wouldn’t sell kids DXM containing cough syrups. Most notably, when they would notice the same kid frequently buying them. This mainly occurred in rural areas, where a given drug store often was the only place nearby a kid could buy DXM containing cough syrups. In those cases, this effectively kept kids from abusing cough syrups. However, in urban areas with numerous stores that sold DXM cough syrups (including the local grocery store), if any pharmacist refused to sell a kid cough syrup the kid could just say “OK, I’ll just walk down the street and buy from your competition.”
As for the situation now, in most areas kids can easily buy DXM containing products. A couple days ago at a CVS there was a sign that Coricidin was available by request only at the counter, and would be sold only to adults. However, there on the shelves were bottles of Robitussin Maximum Strength cough syrup with 354 mg of DXM per bottle, with no added drugs, any kid could pick up and buy. I must make a note to have a chat with the pharmacist about this inconsistency in policy.
I have known one man with a prescription for Jack Daniels bourbon. The guy was 102 years old and having trouble sleeping. His doc prescribed 2 tablespoonfuls of Jack Black every night. The reasoning was that the side effects were minimal, it was cheap, effective, and the old guy liked it. That was back in the early 70s so I have no idea whether this is still done.
On a slight hijack, a recent issue of Scientific American printed a study showing that a specified amount of alcohol every day would drop the risk of a heart attack by over 25%. The amount was about equal to 2 glasses of wine. The interesting point was that doctors have known about this for over a century but never publicised the info for fear of encouraging alcoholism. So, if this study gets repeated a few times we may see more modern docs prescribing a couple of shots of whiskey before bedtime. 
Regards
Testy
My urologist has advised me to drink a beer or two daily, in order to facilitate flushing of the kidneys. A couple of years ago (maybe two or three), doing a stint in the hospital, I asked him if I was allowed to have a beer. He told me I could, but that he’d have to write a scrip for it, and have it brought up from the pharmacy. I told him I didn’t wanna do that, because I’d probably get Bud, and be charged $15.00 for it. He said my best bet was to have my hubby bring me a “beverage of my choice” in a travel mug. This way, the nurses can turn a blind eye, because they don’t know what’s in the mug. I had hubby bring me a Sam Adams. 
I’ve done the same thing with each subsequent hospital stay (usually a couple of times a year).
The only time I’ve heard of it used is for methanol and ethylene glycol poisoning. My Washington Manual even has a maintenance ethanol dosage chart for EG or methanol intoxication based on the drinking history of the patient. At the VA hospital here (the biggest VA), they used to have beer on formulary but they no longer do, instead using benzos or librium for DTs. I believe EtOH infusion also used to be used as a tocolytic – to reverse premature labor. But it isn’t used for that anymore, either.
My grandfather in Israel had a case of kidney stones; his doctor told him to get his wife to pour a six-pack of beer and to drink an equal volume of water in an attempt to clear the stone. He did clear the stone but I don’t know how much the beer had to do with it.
A kid staggers into a drugstore, and asks, “D’you have Rrrromilar CF inna holiday decanter?”
Reminds me of something that happened when we were at the Venice Bistro last Saturday. The Bistro is right on the boardwalk, and we’re sitting there at the bar when a pigeon walks in. It’s like all those jokes.
“A pigeon walks into a bar.”
No punchline…it’s pretty funny by itself when it happens IRL!.