There is plenty of anecdotal evidence ("beer after wine and you'll feel fine, wine after beer will make you feel queer") that mixing alcoholic drink types leads to a stronger effect, but I can't find any true studies.
In fact the only studies I found are looking at mixing energy drinks and alcohol (mixing with energy drinks increases motivation for more alcohol (in college students) [1]), and discussed mixing caffeinated beverages with alcoholic ones [2].
Are there any studies specifically looking at mixing alcoholic drinks? They would have to compare people drinking the same amount of alcohol, but some people mixing, others drinking the same thing. Maybe even a cross-over study design? Same people do both, one after the other? The only way to get an unclouded answer!
I am also interested in the follow-up why question: Why does mixing some drinks make you more drunk? Presumably it is something in wine (for example) that interacts badly with something in beer at the chemical level (the metabolites maybe)?
- Marczinski CA, et al, (2012). Mixing an Energy Drink with an Alcoholic Beverage Increases Motivation for More Alcohol in College Students. Alcohol Clin Exp Res, epub. doi: 10.1111/j.1530-0277.2012.01868.x
- Touyz LZ, (2011). Mixing drinks and concocting troubles. Curr Oncology, 18(6):262-3. PubMed; FullText.