Why is drinking beer after wine a bad idea? As the well known rhyme reminds us, drinking beer after wine is a bad idea. Having made the mistake during my student years more than once and regretting it, why is it that consuming these two beverages in the wrong order causes such effects?
Beer contains a lot of CO2, and CO2 causes the alcohol to 'hit to the head' much faster. This is why champagne has such exhilaration (Rausch) effect. 

It's not a good idea to drink any high-CO2 drink after drinking wine or stronger alcohols, and even more discouraged is mixing carbonated water with vodka, for example. Many people have heavily regret such mixing.

As well, it is said you should never drink lighter alcohols after stronger. You can start with beer, than after an hour/2 drink some wine, rest and drink vodka. Never opposite. But the best is to keep one genre of alcohol on one evening. At least so are saying people in Poland.