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alcoholic beverages, like all food, have inherit properties to go bad. There are sugars in alcoholic beverages that bacteria feed on and will turn something bad when the alcoholic beverage is first exposed to oxygen (IE opened the first time). Wine gets converted to vinegar (acetic acid) Beer changes due to the small yeast content that was used to ferment it in the first place. Alcoholic beverages of greater than 50 proof (25% alcohol content) inherently retard the growth of bacteria due to the high ethanol content. Therefore, the short answer is: It depends. Hard liquor will most likely last much much longer than the less alcoholic drinks.
A couple of things to watch for:
1) Different smell of the beverage, if it's got a different smell, its probably bad.
2) Precipitation, Also known as "floaties": If the liquid is no longer clear then its probably bad.
3) Taste: If its really old give it a sip to make sure it has the same flavor.
I bet the flavored liquors are probably bad if they have been around for 5 years.